Allow new values to be added to an existing enum type.

After much expenditure of effort, we've got this to the point where the
performance penalty is pretty minimal in typical cases.

Andrew Dunstan, reviewed by Brendan Jurd, Dean Rasheed, and Tom Lane
This commit is contained in:
Tom Lane 2010-10-24 23:04:37 -04:00
parent 24b29ca8f9
commit 84c123be1d
23 changed files with 1422 additions and 170 deletions

View File

@ -79,7 +79,7 @@ install_support_functions(void)
"LANGUAGE C STRICT;"));
PQclear(executeQueryOrDie(conn,
"CREATE OR REPLACE FUNCTION "
" binary_upgrade.add_pg_enum_label(OID, OID, NAME) "
" binary_upgrade.set_next_pg_enum_oid(OID) "
"RETURNS VOID "
"AS '$libdir/pg_upgrade_support' "
"LANGUAGE C STRICT;"));

View File

@ -16,13 +16,6 @@
/* THIS IS USED ONLY FOR PG >= 9.0 */
/*
* Cannot include "catalog/pg_enum.h" here because we might
* not be compiling against PG 9.0.
*/
extern void EnumValuesCreate(Oid enumTypeOid, List *vals,
Oid binary_upgrade_next_pg_enum_oid);
#ifdef PG_MODULE_MAGIC
PG_MODULE_MAGIC;
#endif
@ -33,6 +26,7 @@ extern PGDLLIMPORT Oid binary_upgrade_next_pg_type_toast_oid;
extern PGDLLIMPORT Oid binary_upgrade_next_heap_relfilenode;
extern PGDLLIMPORT Oid binary_upgrade_next_toast_relfilenode;
extern PGDLLIMPORT Oid binary_upgrade_next_index_relfilenode;
extern PGDLLIMPORT Oid binary_upgrade_next_pg_enum_oid;
Datum set_next_pg_type_oid(PG_FUNCTION_ARGS);
Datum set_next_pg_type_array_oid(PG_FUNCTION_ARGS);
@ -40,7 +34,7 @@ Datum set_next_pg_type_toast_oid(PG_FUNCTION_ARGS);
Datum set_next_heap_relfilenode(PG_FUNCTION_ARGS);
Datum set_next_toast_relfilenode(PG_FUNCTION_ARGS);
Datum set_next_index_relfilenode(PG_FUNCTION_ARGS);
Datum add_pg_enum_label(PG_FUNCTION_ARGS);
Datum set_next_pg_enum_oid(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(set_next_pg_type_oid);
PG_FUNCTION_INFO_V1(set_next_pg_type_array_oid);
@ -48,7 +42,7 @@ PG_FUNCTION_INFO_V1(set_next_pg_type_toast_oid);
PG_FUNCTION_INFO_V1(set_next_heap_relfilenode);
PG_FUNCTION_INFO_V1(set_next_toast_relfilenode);
PG_FUNCTION_INFO_V1(set_next_index_relfilenode);
PG_FUNCTION_INFO_V1(add_pg_enum_label);
PG_FUNCTION_INFO_V1(set_next_pg_enum_oid);
Datum
set_next_pg_type_oid(PG_FUNCTION_ARGS)
@ -111,14 +105,11 @@ set_next_index_relfilenode(PG_FUNCTION_ARGS)
}
Datum
add_pg_enum_label(PG_FUNCTION_ARGS)
set_next_pg_enum_oid(PG_FUNCTION_ARGS)
{
Oid enumoid = PG_GETARG_OID(0);
Oid typoid = PG_GETARG_OID(1);
Name label = PG_GETARG_NAME(2);
EnumValuesCreate(typoid, list_make1(makeString(NameStr(*label))),
enumoid);
binary_upgrade_next_pg_enum_oid = enumoid;
PG_RETURN_VOID();
}

View File

@ -2623,12 +2623,9 @@
<para>
The <structname>pg_enum</structname> catalog contains entries
matching enum types to their associated values and labels. The
showing the values and labels for each enum type. The
internal representation of a given enum value is actually the OID
of its associated row in <structname>pg_enum</structname>. The
OIDs for a particular enum type are guaranteed to be ordered in
the way the type should sort, but there is no guarantee about the
ordering of OIDs of unrelated enum types.
of its associated row in <structname>pg_enum</structname>.
</para>
<table>
@ -2652,6 +2649,13 @@
<entry>The OID of the <structname>pg_type</> entry owning this enum value</entry>
</row>
<row>
<entry><structfield>enumsortorder</structfield></entry>
<entry><type>float4</type></entry>
<entry></entry>
<entry>The sort position of this enum value within its enum type</entry>
</row>
<row>
<entry><structfield>enumlabel</structfield></entry>
<entry><type>name</type></entry>
@ -2661,6 +2665,26 @@
</tbody>
</tgroup>
</table>
<para>
The OIDs for <structname>pg_enum</structname> rows follow a special
rule: even-numbered OIDs are guaranteed to be ordered in the same way
as the sort ordering of their enum type. That is, if two even OIDs
belong to the same enum type, the smaller OID must have the smaller
<structfield>enumsortorder</structfield> value. Odd-numbered OID values
need bear no relationship to the sort order. This rule allows the
enum comparison routines to avoid catalog lookups in many common cases.
The routines that create and alter enum types attempt to assign even
OIDs to enum values whenever possible.
</para>
<para>
When an enum type is created, its members are assigned sort-order
positions 1..<replaceable>n</>. But members added later might be given
negative or fractional values of <structfield>enumsortorder</structfield>.
The only requirement on these values is that they be correctly
ordered and unique within each enum type.
</para>
</sect1>

View File

@ -24,10 +24,11 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> <replaceable class="PARAMETER">action</replaceable> [, ... ]
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> OWNER TO <replaceable class="PARAMETER">new_owner</replaceable>
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> RENAME ATTRIBUTE <replaceable class="PARAMETER">attribute_name</replaceable> TO <replaceable class="PARAMETER">new_attribute_name</replaceable>
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> RENAME TO <replaceable class="PARAMETER">new_name</replaceable>
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replaceable class="PARAMETER">new_schema</replaceable>
ALTER TYPE <replaceable class="PARAMETER">name</replaceable> ADD <replaceable class="PARAMETER">new_enum_value</replaceable> [ { BEFORE | AFTER } <replaceable class="PARAMETER">existing_enum_value</replaceable> ]
<phrase>where <replaceable class="PARAMETER">action</replaceable> is one of:</phrase>
@ -103,6 +104,18 @@ ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replace
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>ADD [ BEFORE | AFTER ]</literal></term>
<listitem>
<para>
This form adds a new value to an enum type. If the new value's place in
the enum's ordering is not specified using <literal>BEFORE</literal> or
<literal>AFTER</literal>, then the new item is placed at the end of the
list of values.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
@ -181,7 +194,7 @@ ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replace
<term><replaceable class="PARAMETER">new_attribute_name</replaceable></term>
<listitem>
<para>
The new name of the attribute begin renamed.
The new name of the attribute to be renamed.
</para>
</listitem>
</varlistentry>
@ -196,10 +209,53 @@ ALTER TYPE <replaceable class="PARAMETER">name</replaceable> SET SCHEMA <replace
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">new_enum_value</replaceable></term>
<listitem>
<para>
The new value to be added to an enum type's list of values.
Like all enum literals, it needs to be quoted.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="PARAMETER">existing_enum_value</replaceable></term>
<listitem>
<para>
The existing enum value that the new value should be added immediately
before or after in the enum type's sort ordering.
Like all enum literals, it needs to be quoted.
</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</refsect1>
<refsect1>
<title>Notes</title>
<para>
<command>ALTER TYPE ... ADD</> (the form that adds a new value to an
enum type) cannot be executed inside a transaction block.
</para>
<para>
Comparisons involving an added enum value will sometimes be slower than
comparisons involving only original members of the enum type. This will
usually only occur if <literal>BEFORE</literal> or <literal>AFTER</literal>
is used to set the new value's sort position somewhere other than at the
end of the list. However, sometimes it will happen even though the new
value is added at the end (this occurs if the OID counter <quote>wrapped
around</> since the original creation of the enum type). The slowdown is
usually insignificant; but if it matters, optimal performance can be
regained by dropping and recreating the enum type, or by dumping and
reloading the database.
</para>
</refsect1>
<refsect1>
<title>Examples</title>
@ -230,6 +286,13 @@ ALTER TYPE email SET SCHEMA customers;
To add a new attribute to a type:
<programlisting>
ALTER TYPE compfoo ADD ATTRIBUTE f3 int;
</programlisting>
</para>
<para>
To add a new value to an enum type in a particular sort position:
<programlisting>
ALTER TYPE colors ADD 'orange' AFTER 'red';
</programlisting>
</para>
</refsect1>

View File

@ -15,15 +15,24 @@
#include "access/genam.h"
#include "access/heapam.h"
#include "access/xact.h"
#include "catalog/catalog.h"
#include "catalog/indexing.h"
#include "catalog/pg_enum.h"
#include "catalog/pg_type.h"
#include "storage/lmgr.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/rel.h"
#include "utils/syscache.h"
#include "utils/tqual.h"
Oid binary_upgrade_next_pg_enum_oid = InvalidOid;
static void RenumberEnumType(Relation pg_enum, HeapTuple *existing, int nelems);
static int oid_cmp(const void *p1, const void *p2);
static int sort_order_cmp(const void *p1, const void *p2);
/*
@ -33,11 +42,9 @@ static int oid_cmp(const void *p1, const void *p2);
* vals is a list of Value strings.
*/
void
EnumValuesCreate(Oid enumTypeOid, List *vals,
Oid binary_upgrade_next_pg_enum_oid)
EnumValuesCreate(Oid enumTypeOid, List *vals)
{
Relation pg_enum;
TupleDesc tupDesc;
NameData enumlabel;
Oid *oids;
int elemno,
@ -50,48 +57,42 @@ EnumValuesCreate(Oid enumTypeOid, List *vals,
num_elems = list_length(vals);
/*
* XXX we do not bother to check the list of values for duplicates --- if
* We do not bother to check the list of values for duplicates --- if
* you have any, you'll get a less-than-friendly unique-index violation.
* Is it worth trying harder?
* It is probably not worth trying harder.
*/
pg_enum = heap_open(EnumRelationId, RowExclusiveLock);
tupDesc = pg_enum->rd_att;
/*
* Allocate oids
* Allocate OIDs for the enum's members.
*
* While this method does not absolutely guarantee that we generate no
* duplicate OIDs (since we haven't entered each oid into the table
* before allocating the next), trouble could only occur if the OID
* counter wraps all the way around before we finish. Which seems
* unlikely.
*/
oids = (Oid *) palloc(num_elems * sizeof(Oid));
if (OidIsValid(binary_upgrade_next_pg_enum_oid))
{
if (num_elems != 1)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("EnumValuesCreate() can only set a single OID")));
oids[0] = binary_upgrade_next_pg_enum_oid;
binary_upgrade_next_pg_enum_oid = InvalidOid;
}
else
for (elemno = 0; elemno < num_elems; elemno++)
{
/*
* While this method does not absolutely guarantee that we generate no
* duplicate oids (since we haven't entered each oid into the table
* before allocating the next), trouble could only occur if the oid
* counter wraps all the way around before we finish. Which seems
* unlikely.
* We assign even-numbered OIDs to all the new enum labels. This
* tells the comparison functions the OIDs are in the correct sort
* order and can be compared directly.
*/
for (elemno = 0; elemno < num_elems; elemno++)
{
/*
* The pg_enum.oid is stored in user tables. This oid must be
* preserved by binary upgrades.
*/
oids[elemno] = GetNewOid(pg_enum);
}
/* sort them, just in case counter wrapped from high to low */
qsort(oids, num_elems, sizeof(Oid), oid_cmp);
Oid new_oid;
do {
new_oid = GetNewOid(pg_enum);
} while (new_oid & 1);
oids[elemno] = new_oid;
}
/* sort them, just in case OID counter wrapped from high to low */
qsort(oids, num_elems, sizeof(Oid), oid_cmp);
/* and make the entries */
memset(nulls, false, sizeof(nulls));
@ -112,10 +113,11 @@ EnumValuesCreate(Oid enumTypeOid, List *vals,
NAMEDATALEN - 1)));
values[Anum_pg_enum_enumtypid - 1] = ObjectIdGetDatum(enumTypeOid);
values[Anum_pg_enum_enumsortorder - 1] = Float4GetDatum(elemno + 1);
namestrcpy(&enumlabel, lab);
values[Anum_pg_enum_enumlabel - 1] = NameGetDatum(&enumlabel);
tup = heap_form_tuple(tupDesc, values, nulls);
tup = heap_form_tuple(RelationGetDescr(pg_enum), values, nulls);
HeapTupleSetOid(tup, oids[elemno]);
simple_heap_insert(pg_enum, tup);
@ -164,7 +166,322 @@ EnumValuesDelete(Oid enumTypeOid)
}
/* qsort comparison function */
/*
* AddEnumLabel
* Add a new label to the enum set. By default it goes at
* the end, but the user can choose to place it before or
* after any existing set member.
*/
void
AddEnumLabel(Oid enumTypeOid,
const char *newVal,
const char *neighbor,
bool newValIsAfter)
{
Relation pg_enum;
Oid newOid;
Datum values[Natts_pg_enum];
bool nulls[Natts_pg_enum];
NameData enumlabel;
HeapTuple enum_tup;
float4 newelemorder;
HeapTuple *existing;
CatCList *list;
int nelems;
int i;
/* check length of new label is ok */
if (strlen(newVal) > (NAMEDATALEN - 1))
ereport(ERROR,
(errcode(ERRCODE_INVALID_NAME),
errmsg("invalid enum label \"%s\"", newVal),
errdetail("Labels must be %d characters or less.",
NAMEDATALEN - 1)));
/*
* Acquire a lock on the enum type, which we won't release until commit.
* This ensures that two backends aren't concurrently modifying the same
* enum type. Without that, we couldn't be sure to get a consistent
* view of the enum members via the syscache. Note that this does not
* block other backends from inspecting the type; see comments for
* RenumberEnumType.
*/
LockDatabaseObject(TypeRelationId, enumTypeOid, 0, ExclusiveLock);
pg_enum = heap_open(EnumRelationId, RowExclusiveLock);
/* If we have to renumber the existing members, we restart from here */
restart:
/* Get the list of existing members of the enum */
list = SearchSysCacheList1(ENUMTYPOIDNAME,
ObjectIdGetDatum(enumTypeOid));
nelems = list->n_members;
/* Sort the existing members by enumsortorder */
existing = (HeapTuple *) palloc(nelems * sizeof(HeapTuple));
for (i = 0; i < nelems; i++)
existing[i] = &(list->members[i]->tuple);
qsort(existing, nelems, sizeof(HeapTuple), sort_order_cmp);
if (neighbor == NULL)
{
/*
* Put the new label at the end of the list.
* No change to existing tuples is required.
*/
if (nelems > 0)
{
Form_pg_enum en = (Form_pg_enum) GETSTRUCT(existing[nelems - 1]);
newelemorder = en->enumsortorder + 1;
}
else
newelemorder = 1;
}
else
{
/* BEFORE or AFTER was specified */
int nbr_index;
int other_nbr_index;
Form_pg_enum nbr_en;
Form_pg_enum other_nbr_en;
/* Locate the neighbor element */
for (nbr_index = 0; nbr_index < nelems; nbr_index++)
{
Form_pg_enum en = (Form_pg_enum) GETSTRUCT(existing[nbr_index]);
if (strcmp(NameStr(en->enumlabel), neighbor) == 0)
break;
}
if (nbr_index >= nelems)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("\"%s\" is not an existing enum label",
neighbor)));
nbr_en = (Form_pg_enum) GETSTRUCT(existing[nbr_index]);
/*
* Attempt to assign an appropriate enumsortorder value: one less
* than the smallest member, one more than the largest member,
* or halfway between two existing members.
*
* In the "halfway" case, because of the finite precision of float4,
* we might compute a value that's actually equal to one or the
* other of its neighbors. In that case we renumber the existing
* members and try again.
*/
if (newValIsAfter)
other_nbr_index = nbr_index + 1;
else
other_nbr_index = nbr_index - 1;
if (other_nbr_index < 0)
newelemorder = nbr_en->enumsortorder - 1;
else if (other_nbr_index >= nelems)
newelemorder = nbr_en->enumsortorder + 1;
else
{
other_nbr_en = (Form_pg_enum) GETSTRUCT(existing[other_nbr_index]);
newelemorder = (nbr_en->enumsortorder +
other_nbr_en->enumsortorder) / 2;
if (newelemorder == nbr_en->enumsortorder ||
newelemorder == other_nbr_en->enumsortorder)
{
RenumberEnumType(pg_enum, existing, nelems);
/* Clean up and start over */
pfree(existing);
ReleaseCatCacheList(list);
goto restart;
}
}
}
/* Get a new OID for the new label */
if (OidIsValid(binary_upgrade_next_pg_enum_oid))
{
/*
* In binary upgrades, just add the new label with the predetermined
* Oid. It's pg_upgrade's responsibility that the Oid meets
* requirements.
*/
if (neighbor != NULL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("ALTER TYPE ADD BEFORE/AFTER is incompatible with binary upgrade")));
newOid = binary_upgrade_next_pg_enum_oid;
binary_upgrade_next_pg_enum_oid = InvalidOid;
}
else
{
/*
* Normal case: we need to allocate a new Oid for the value.
*
* We want to give the new element an even-numbered Oid if it's safe,
* which is to say it compares correctly to all pre-existing even
* numbered Oids in the enum. Otherwise, we must give it an odd Oid.
*/
for (;;)
{
bool sorts_ok;
/* Get a new OID (different from all existing pg_enum tuples) */
newOid = GetNewOid(pg_enum);
/*
* Detect whether it sorts correctly relative to existing
* even-numbered labels of the enum. We can ignore existing
* labels with odd Oids, since a comparison involving one of
* those will not take the fast path anyway.
*/
sorts_ok = true;
for (i = 0; i < nelems; i++)
{
HeapTuple exists_tup = existing[i];
Form_pg_enum exists_en = (Form_pg_enum) GETSTRUCT(exists_tup);
Oid exists_oid = HeapTupleGetOid(exists_tup);
if (exists_oid & 1)
continue; /* ignore odd Oids */
if (exists_en->enumsortorder < newelemorder)
{
/* should sort before */
if (exists_oid >= newOid)
{
sorts_ok = false;
break;
}
}
else
{
/* should sort after */
if (exists_oid <= newOid)
{
sorts_ok = false;
break;
}
}
}
if (sorts_ok)
{
/* If it's even and sorts OK, we're done. */
if ((newOid & 1) == 0)
break;
/*
* If it's odd, and sorts OK, loop back to get another OID
* and try again. Probably, the next available even OID
* will sort correctly too, so it's worth trying.
*/
}
else
{
/*
* If it's odd, and does not sort correctly, we're done.
* (Probably, the next available even OID would sort
* incorrectly too, so no point in trying again.)
*/
if (newOid & 1)
break;
/*
* If it's even, and does not sort correctly, loop back to get
* another OID and try again. (We *must* reject this case.)
*/
}
}
}
/* Done with info about existing members */
pfree(existing);
ReleaseCatCacheList(list);
/* Create the new pg_enum entry */
memset(nulls, false, sizeof(nulls));
values[Anum_pg_enum_enumtypid - 1] = ObjectIdGetDatum(enumTypeOid);
values[Anum_pg_enum_enumsortorder - 1] = Float4GetDatum(newelemorder);
namestrcpy(&enumlabel, newVal);
values[Anum_pg_enum_enumlabel - 1] = NameGetDatum(&enumlabel);
enum_tup = heap_form_tuple(RelationGetDescr(pg_enum), values, nulls);
HeapTupleSetOid(enum_tup, newOid);
simple_heap_insert(pg_enum, enum_tup);
CatalogUpdateIndexes(pg_enum, enum_tup);
heap_freetuple(enum_tup);
heap_close(pg_enum, RowExclusiveLock);
}
/*
* RenumberEnumType
* Renumber existing enum elements to have sort positions 1..n.
*
* We avoid doing this unless absolutely necessary; in most installations
* it will never happen. The reason is that updating existing pg_enum
* entries creates hazards for other backends that are concurrently reading
* pg_enum with SnapshotNow semantics. A concurrent SnapshotNow scan could
* see both old and new versions of an updated row as valid, or neither of
* them, if the commit happens between scanning the two versions. It's
* also quite likely for a concurrent scan to see an inconsistent set of
* rows (some members updated, some not).
*
* We can avoid these risks by reading pg_enum with an MVCC snapshot
* instead of SnapshotNow, but that forecloses use of the syscaches.
* We therefore make the following choices:
*
* 1. Any code that is interested in the enumsortorder values MUST read
* pg_enum with an MVCC snapshot, or else acquire lock on the enum type
* to prevent concurrent execution of AddEnumLabel(). The risk of
* seeing inconsistent values of enumsortorder is too high otherwise.
*
* 2. Code that is not examining enumsortorder can use a syscache
* (for example, enum_in and enum_out do so). The worst that can happen
* is a transient failure to find any valid value of the row. This is
* judged acceptable in view of the infrequency of use of RenumberEnumType.
*/
static void
RenumberEnumType(Relation pg_enum, HeapTuple *existing, int nelems)
{
int i;
/*
* We should only need to increase existing elements' enumsortorders,
* never decrease them. Therefore, work from the end backwards, to avoid
* unwanted uniqueness violations.
*/
for (i = nelems - 1; i >= 0; i--)
{
HeapTuple newtup;
Form_pg_enum en;
float4 newsortorder;
newtup = heap_copytuple(existing[i]);
en = (Form_pg_enum) GETSTRUCT(newtup);
newsortorder = i + 1;
if (en->enumsortorder != newsortorder)
{
en->enumsortorder = newsortorder;
simple_heap_update(pg_enum, &newtup->t_self, newtup);
CatalogUpdateIndexes(pg_enum, newtup);
}
heap_freetuple(newtup);
}
/* Make the updates visible */
CommandCounterIncrement();
}
/* qsort comparison function for oids */
static int
oid_cmp(const void *p1, const void *p2)
{
@ -177,3 +494,20 @@ oid_cmp(const void *p1, const void *p2)
return 1;
return 0;
}
/* qsort comparison function for tuples by sort order */
static int
sort_order_cmp(const void *p1, const void *p2)
{
HeapTuple v1 = *((const HeapTuple *) p1);
HeapTuple v2 = *((const HeapTuple *) p2);
Form_pg_enum en1 = (Form_pg_enum) GETSTRUCT(v1);
Form_pg_enum en2 = (Form_pg_enum) GETSTRUCT(v2);
if (en1->enumsortorder < en2->enumsortorder)
return -1;
else if (en1->enumsortorder > en2->enumsortorder)
return 1;
else
return 0;
}

View File

@ -84,7 +84,8 @@ static Oid findTypeTypmodinFunction(List *procname);
static Oid findTypeTypmodoutFunction(List *procname);
static Oid findTypeAnalyzeFunction(List *procname, Oid typeOid);
static List *get_rels_with_domain(Oid domainOid, LOCKMODE lockmode);
static void checkDomainOwner(HeapTuple tup, TypeName *typename);
static void checkDomainOwner(HeapTuple tup);
static void checkEnumOwner(HeapTuple tup);
static char *domainAddConstraint(Oid domainOid, Oid domainNamespace,
Oid baseTypeOid,
int typMod, Constraint *constr,
@ -1150,7 +1151,7 @@ DefineEnum(CreateEnumStmt *stmt)
false); /* Type NOT NULL */
/* Enter the enum's values into pg_enum */
EnumValuesCreate(enumTypeOid, stmt->vals, InvalidOid);
EnumValuesCreate(enumTypeOid, stmt->vals);
/*
* Create the array type that goes with it.
@ -1191,6 +1192,60 @@ DefineEnum(CreateEnumStmt *stmt)
pfree(enumArrayName);
}
/*
* AlterEnum
* Adds a new label to an existing enum.
*/
void
AlterEnum(AlterEnumStmt *stmt)
{
Oid enum_type_oid;
TypeName *typename;
HeapTuple tup;
/* Make a TypeName so we can use standard type lookup machinery */
typename = makeTypeNameFromNameList(stmt->typeName);
enum_type_oid = typenameTypeId(NULL, typename, NULL);
tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(enum_type_oid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for type %u", enum_type_oid);
/* Check it's an enum and check user has permission to ALTER the enum */
checkEnumOwner(tup);
/* Add the new label */
AddEnumLabel(enum_type_oid, stmt->newVal,
stmt->newValNeighbor, stmt->newValIsAfter);
ReleaseSysCache(tup);
}
/*
* checkEnumOwner
*
* Check that the type is actually an enum and that the current user
* has permission to do ALTER TYPE on it. Throw an error if not.
*/
static void
checkEnumOwner(HeapTuple tup)
{
Form_pg_type typTup = (Form_pg_type) GETSTRUCT(tup);
/* Check that this is actually an enum */
if (typTup->typtype != TYPTYPE_ENUM)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("%s is not an enum",
format_type_be(HeapTupleGetOid(tup)))));
/* Permission check: must own type */
if (!pg_type_ownercheck(HeapTupleGetOid(tup), GetUserId()))
aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_TYPE,
format_type_be(HeapTupleGetOid(tup)));
}
/*
* Find suitable I/O functions for a type.
@ -1576,7 +1631,7 @@ AlterDomainDefault(List *names, Node *defaultRaw)
typTup = (Form_pg_type) GETSTRUCT(tup);
/* Check it's a domain and check user has permission for ALTER DOMAIN */
checkDomainOwner(tup, typename);
checkDomainOwner(tup);
/* Setup new tuple */
MemSet(new_record, (Datum) 0, sizeof(new_record));
@ -1702,7 +1757,7 @@ AlterDomainNotNull(List *names, bool notNull)
typTup = (Form_pg_type) GETSTRUCT(tup);
/* Check it's a domain and check user has permission for ALTER DOMAIN */
checkDomainOwner(tup, typename);
checkDomainOwner(tup);
/* Is the domain already set to the desired constraint? */
if (typTup->typnotnull == notNull)
@ -1801,7 +1856,7 @@ AlterDomainDropConstraint(List *names, const char *constrName,
elog(ERROR, "cache lookup failed for type %u", domainoid);
/* Check it's a domain and check user has permission for ALTER DOMAIN */
checkDomainOwner(tup, typename);
checkDomainOwner(tup);
/* Grab an appropriate lock on the pg_constraint relation */
conrel = heap_open(ConstraintRelationId, RowExclusiveLock);
@ -1875,7 +1930,7 @@ AlterDomainAddConstraint(List *names, Node *newConstraint)
typTup = (Form_pg_type) GETSTRUCT(tup);
/* Check it's a domain and check user has permission for ALTER DOMAIN */
checkDomainOwner(tup, typename);
checkDomainOwner(tup);
if (!IsA(newConstraint, Constraint))
elog(ERROR, "unrecognized node type: %d",
@ -2187,7 +2242,7 @@ get_rels_with_domain(Oid domainOid, LOCKMODE lockmode)
* has permission to do ALTER DOMAIN on it. Throw an error if not.
*/
static void
checkDomainOwner(HeapTuple tup, TypeName *typename)
checkDomainOwner(HeapTuple tup)
{
Form_pg_type typTup = (Form_pg_type) GETSTRUCT(tup);
@ -2195,8 +2250,8 @@ checkDomainOwner(HeapTuple tup, TypeName *typename)
if (typTup->typtype != TYPTYPE_DOMAIN)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a domain",
TypeNameToString(typename))));
errmsg("%s is not a domain",
format_type_be(HeapTupleGetOid(tup)))));
/* Permission check: must own type */
if (!pg_type_ownercheck(HeapTupleGetOid(tup), GetUserId()))

View File

@ -2901,6 +2901,19 @@ _copyCreateEnumStmt(CreateEnumStmt *from)
return newnode;
}
static AlterEnumStmt *
_copyAlterEnumStmt(AlterEnumStmt *from)
{
AlterEnumStmt *newnode = makeNode(AlterEnumStmt);
COPY_NODE_FIELD(typeName);
COPY_STRING_FIELD(newVal);
COPY_STRING_FIELD(newValNeighbor);
COPY_SCALAR_FIELD(newValIsAfter);
return newnode;
}
static ViewStmt *
_copyViewStmt(ViewStmt *from)
{
@ -4064,6 +4077,9 @@ copyObject(void *from)
case T_CreateEnumStmt:
retval = _copyCreateEnumStmt(from);
break;
case T_AlterEnumStmt:
retval = _copyAlterEnumStmt(from);
break;
case T_ViewStmt:
retval = _copyViewStmt(from);
break;

View File

@ -1392,6 +1392,17 @@ _equalCreateEnumStmt(CreateEnumStmt *a, CreateEnumStmt *b)
return true;
}
static bool
_equalAlterEnumStmt(AlterEnumStmt *a, AlterEnumStmt *b)
{
COMPARE_NODE_FIELD(typeName);
COMPARE_STRING_FIELD(newVal);
COMPARE_STRING_FIELD(newValNeighbor);
COMPARE_SCALAR_FIELD(newValIsAfter);
return true;
}
static bool
_equalViewStmt(ViewStmt *a, ViewStmt *b)
{
@ -2700,6 +2711,9 @@ equal(void *a, void *b)
case T_CreateEnumStmt:
retval = _equalCreateEnumStmt(a, b);
break;
case T_AlterEnumStmt:
retval = _equalAlterEnumStmt(a, b);
break;
case T_ViewStmt:
retval = _equalViewStmt(a, b);
break;

View File

@ -182,8 +182,8 @@ static RangeVar *makeRangeVarFromAnyName(List *names, int position, core_yyscan_
}
%type <node> stmt schema_stmt
AlterDatabaseStmt AlterDatabaseSetStmt AlterDomainStmt AlterFdwStmt
AlterForeignServerStmt AlterGroupStmt
AlterDatabaseStmt AlterDatabaseSetStmt AlterDomainStmt AlterEnumStmt
AlterFdwStmt AlterForeignServerStmt AlterGroupStmt
AlterObjectSchemaStmt AlterOwnerStmt AlterSeqStmt AlterTableStmt
AlterCompositeTypeStmt AlterUserStmt AlterUserMappingStmt AlterUserSetStmt
AlterRoleStmt AlterRoleSetStmt
@ -652,6 +652,7 @@ stmt :
| AlterDatabaseSetStmt
| AlterDefaultPrivilegesStmt
| AlterDomainStmt
| AlterEnumStmt
| AlterFdwStmt
| AlterForeignServerStmt
| AlterFunctionStmt
@ -3863,6 +3864,42 @@ enum_val_list: Sconst
{ $$ = lappend($1, makeString($3)); }
;
/*****************************************************************************
*
* ALTER TYPE enumtype ADD ...
*
*****************************************************************************/
AlterEnumStmt:
ALTER TYPE_P any_name ADD_P Sconst
{
AlterEnumStmt *n = makeNode(AlterEnumStmt);
n->typeName = $3;
n->newVal = $5;
n->newValNeighbor = NULL;
n->newValIsAfter = true;
$$ = (Node *) n;
}
| ALTER TYPE_P any_name ADD_P Sconst BEFORE Sconst
{
AlterEnumStmt *n = makeNode(AlterEnumStmt);
n->typeName = $3;
n->newVal = $5;
n->newValNeighbor = $7;
n->newValIsAfter = false;
$$ = (Node *) n;
}
| ALTER TYPE_P any_name ADD_P Sconst AFTER Sconst
{
AlterEnumStmt *n = makeNode(AlterEnumStmt);
n->typeName = $3;
n->newVal = $5;
n->newValNeighbor = $7;
n->newValIsAfter = true;
$$ = (Node *) n;
}
;
/*****************************************************************************
*

View File

@ -190,6 +190,7 @@ check_xact_readonly(Node *parsetree)
case T_CreateTrigStmt:
case T_CompositeTypeStmt:
case T_CreateEnumStmt:
case T_AlterEnumStmt:
case T_ViewStmt:
case T_DropCastStmt:
case T_DropStmt:
@ -860,6 +861,16 @@ standard_ProcessUtility(Node *parsetree,
DefineEnum((CreateEnumStmt *) parsetree);
break;
case T_AlterEnumStmt: /* ALTER TYPE (enum) */
/*
* We disallow this in transaction blocks, because we can't cope
* with enum OID values getting into indexes and then having their
* defining pg_enum entries go away.
*/
PreventTransactionChain(isTopLevel, "ALTER TYPE ... ADD");
AlterEnum((AlterEnumStmt *) parsetree);
break;
case T_ViewStmt: /* CREATE VIEW */
DefineView((ViewStmt *) parsetree, queryString);
break;
@ -1868,6 +1879,10 @@ CreateCommandTag(Node *parsetree)
tag = "CREATE TYPE";
break;
case T_AlterEnumStmt:
tag = "ALTER TYPE";
break;
case T_ViewStmt:
tag = "CREATE VIEW";
break;
@ -2410,6 +2425,10 @@ GetCommandLogLevel(Node *parsetree)
lev = LOGSTMT_DDL;
break;
case T_AlterEnumStmt:
lev = LOGSTMT_DDL;
break;
case T_ViewStmt:
lev = LOGSTMT_DDL;
break;

View File

@ -13,18 +13,22 @@
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "catalog/indexing.h"
#include "catalog/pg_enum.h"
#include "fmgr.h"
#include "libpq/pqformat.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/lsyscache.h"
#include "utils/fmgroids.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "libpq/pqformat.h"
#include "miscadmin.h"
#include "utils/typcache.h"
static Oid enum_endpoint(Oid enumtypoid, ScanDirection direction);
static ArrayType *enum_range_internal(Oid enumtypoid, Oid lower, Oid upper);
static int enum_elem_cmp(const void *left, const void *right);
/* Basic I/O support */
@ -155,13 +159,63 @@ enum_send(PG_FUNCTION_ARGS)
/* Comparison functions and related */
/*
* enum_cmp_internal is the common engine for all the visible comparison
* functions, except for enum_eq and enum_ne which can just check for OID
* equality directly.
*/
static int
enum_cmp_internal(Oid arg1, Oid arg2, FunctionCallInfo fcinfo)
{
TypeCacheEntry *tcache;
/* Equal OIDs are equal no matter what */
if (arg1 == arg2)
return 0;
/* Fast path: even-numbered Oids are known to compare correctly */
if ((arg1 & 1) == 0 && (arg2 & 1) == 0)
{
if (arg1 < arg2)
return -1;
else
return 1;
}
/* Locate the typcache entry for the enum type */
tcache = (TypeCacheEntry *) fcinfo->flinfo->fn_extra;
if (tcache == NULL)
{
HeapTuple enum_tup;
Form_pg_enum en;
Oid typeoid;
/* Get the OID of the enum type containing arg1 */
enum_tup = SearchSysCache1(ENUMOID, ObjectIdGetDatum(arg1));
if (!HeapTupleIsValid(enum_tup))
ereport(ERROR,
(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
errmsg("invalid internal value for enum: %u",
arg1)));
en = (Form_pg_enum) GETSTRUCT(enum_tup);
typeoid = en->enumtypid;
ReleaseSysCache(enum_tup);
/* Now locate and remember the typcache entry */
tcache = lookup_type_cache(typeoid, 0);
fcinfo->flinfo->fn_extra = (void *) tcache;
}
/* The remaining comparison logic is in typcache.c */
return compare_values_of_enum(tcache, arg1, arg2);
}
Datum
enum_lt(PG_FUNCTION_ARGS)
{
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
PG_RETURN_BOOL(a < b);
PG_RETURN_BOOL(enum_cmp_internal(a, b, fcinfo) < 0);
}
Datum
@ -170,7 +224,7 @@ enum_le(PG_FUNCTION_ARGS)
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
PG_RETURN_BOOL(a <= b);
PG_RETURN_BOOL(enum_cmp_internal(a, b, fcinfo) <= 0);
}
Datum
@ -197,7 +251,7 @@ enum_ge(PG_FUNCTION_ARGS)
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
PG_RETURN_BOOL(a >= b);
PG_RETURN_BOOL(enum_cmp_internal(a, b, fcinfo) >= 0);
}
Datum
@ -206,7 +260,7 @@ enum_gt(PG_FUNCTION_ARGS)
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
PG_RETURN_BOOL(a > b);
PG_RETURN_BOOL(enum_cmp_internal(a, b, fcinfo) > 0);
}
Datum
@ -215,7 +269,7 @@ enum_smaller(PG_FUNCTION_ARGS)
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
PG_RETURN_OID(a <= b ? a : b);
PG_RETURN_OID(enum_cmp_internal(a, b, fcinfo) < 0 ? a : b);
}
Datum
@ -224,7 +278,7 @@ enum_larger(PG_FUNCTION_ARGS)
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
PG_RETURN_OID(a >= b ? a : b);
PG_RETURN_OID(enum_cmp_internal(a, b, fcinfo) > 0 ? a : b);
}
Datum
@ -233,24 +287,63 @@ enum_cmp(PG_FUNCTION_ARGS)
Oid a = PG_GETARG_OID(0);
Oid b = PG_GETARG_OID(1);
if (a > b)
PG_RETURN_INT32(1);
else if (a == b)
if (a == b)
PG_RETURN_INT32(0);
else if (enum_cmp_internal(a, b, fcinfo) > 0)
PG_RETURN_INT32(1);
else
PG_RETURN_INT32(-1);
}
/* Enum programming support functions */
/*
* enum_endpoint: common code for enum_first/enum_last
*/
static Oid
enum_endpoint(Oid enumtypoid, ScanDirection direction)
{
Relation enum_rel;
Relation enum_idx;
SysScanDesc enum_scan;
HeapTuple enum_tuple;
ScanKeyData skey;
Oid minmax;
/*
* Find the first/last enum member using pg_enum_typid_sortorder_index.
* Note we must not use the syscache, and must use an MVCC snapshot here.
* See comments for RenumberEnumType in catalog/pg_enum.c for more info.
*/
ScanKeyInit(&skey,
Anum_pg_enum_enumtypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(enumtypoid));
enum_rel = heap_open(EnumRelationId, AccessShareLock);
enum_idx = index_open(EnumTypIdSortOrderIndexId, AccessShareLock);
enum_scan = systable_beginscan_ordered(enum_rel, enum_idx,
GetTransactionSnapshot(),
1, &skey);
enum_tuple = systable_getnext_ordered(enum_scan, direction);
if (HeapTupleIsValid(enum_tuple))
minmax = HeapTupleGetOid(enum_tuple);
else
minmax = InvalidOid;
systable_endscan_ordered(enum_scan);
index_close(enum_idx, AccessShareLock);
heap_close(enum_rel, AccessShareLock);
return minmax;
}
Datum
enum_first(PG_FUNCTION_ARGS)
{
Oid enumtypoid;
Oid min = InvalidOid;
CatCList *list;
int num,
i;
Oid min;
/*
* We rely on being able to get the specific enum type from the calling
@ -263,21 +356,14 @@ enum_first(PG_FUNCTION_ARGS)
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("could not determine actual enum type")));
list = SearchSysCacheList1(ENUMTYPOIDNAME, ObjectIdGetDatum(enumtypoid));
num = list->n_members;
for (i = 0; i < num; i++)
{
Oid valoid = HeapTupleHeaderGetOid(list->members[i]->tuple.t_data);
/* Get the OID using the index */
min = enum_endpoint(enumtypoid, ForwardScanDirection);
if (!OidIsValid(min) || valoid < min)
min = valoid;
}
ReleaseCatCacheList(list);
if (!OidIsValid(min)) /* should not happen */
elog(ERROR, "no values found for enum %s",
format_type_be(enumtypoid));
if (!OidIsValid(min))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("enum %s contains no values",
format_type_be(enumtypoid))));
PG_RETURN_OID(min);
}
@ -286,10 +372,7 @@ Datum
enum_last(PG_FUNCTION_ARGS)
{
Oid enumtypoid;
Oid max = InvalidOid;
CatCList *list;
int num,
i;
Oid max;
/*
* We rely on being able to get the specific enum type from the calling
@ -302,21 +385,14 @@ enum_last(PG_FUNCTION_ARGS)
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("could not determine actual enum type")));
list = SearchSysCacheList1(ENUMTYPOIDNAME, ObjectIdGetDatum(enumtypoid));
num = list->n_members;
for (i = 0; i < num; i++)
{
Oid valoid = HeapTupleHeaderGetOid(list->members[i]->tuple.t_data);
/* Get the OID using the index */
max = enum_endpoint(enumtypoid, BackwardScanDirection);
if (!OidIsValid(max) || valoid > max)
max = valoid;
}
ReleaseCatCacheList(list);
if (!OidIsValid(max)) /* should not happen */
elog(ERROR, "no values found for enum %s",
format_type_be(enumtypoid));
if (!OidIsValid(max))
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("enum %s contains no values",
format_type_be(enumtypoid))));
PG_RETURN_OID(max);
}
@ -377,51 +453,68 @@ static ArrayType *
enum_range_internal(Oid enumtypoid, Oid lower, Oid upper)
{
ArrayType *result;
CatCList *list;
int total,
i,
j;
Relation enum_rel;
Relation enum_idx;
SysScanDesc enum_scan;
HeapTuple enum_tuple;
ScanKeyData skey;
Datum *elems;
int max,
cnt;
bool left_found;
list = SearchSysCacheList1(ENUMTYPOIDNAME, ObjectIdGetDatum(enumtypoid));
total = list->n_members;
/*
* Scan the enum members in order using pg_enum_typid_sortorder_index.
* Note we must not use the syscache, and must use an MVCC snapshot here.
* See comments for RenumberEnumType in catalog/pg_enum.c for more info.
*/
ScanKeyInit(&skey,
Anum_pg_enum_enumtypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(enumtypoid));
elems = (Datum *) palloc(total * sizeof(Datum));
enum_rel = heap_open(EnumRelationId, AccessShareLock);
enum_idx = index_open(EnumTypIdSortOrderIndexId, AccessShareLock);
enum_scan = systable_beginscan_ordered(enum_rel, enum_idx,
GetTransactionSnapshot(),
1, &skey);
j = 0;
for (i = 0; i < total; i++)
max = 64;
elems = (Datum *) palloc(max * sizeof(Datum));
cnt = 0;
left_found = !OidIsValid(lower);
while (HeapTupleIsValid(enum_tuple = systable_getnext_ordered(enum_scan, ForwardScanDirection)))
{
Oid val = HeapTupleGetOid(&(list->members[i]->tuple));
Oid enum_oid = HeapTupleGetOid(enum_tuple);
if ((!OidIsValid(lower) || lower <= val) &&
(!OidIsValid(upper) || val <= upper))
elems[j++] = ObjectIdGetDatum(val);
if (!left_found && lower == enum_oid)
left_found = true;
if (left_found)
{
if (cnt >= max)
{
max *= 2;
elems = (Datum *) repalloc(elems, max * sizeof(Datum));
}
elems[cnt++] = ObjectIdGetDatum(enum_oid);
}
if (OidIsValid(upper) && upper == enum_oid)
break;
}
/* shouldn't need the cache anymore */
ReleaseCatCacheList(list);
/* sort results into OID order */
qsort(elems, j, sizeof(Datum), enum_elem_cmp);
systable_endscan_ordered(enum_scan);
index_close(enum_idx, AccessShareLock);
heap_close(enum_rel, AccessShareLock);
/* and build the result array */
/* note this hardwires some details about the representation of Oid */
result = construct_array(elems, j, enumtypoid, sizeof(Oid), true, 'i');
result = construct_array(elems, cnt, enumtypoid, sizeof(Oid), true, 'i');
pfree(elems);
return result;
}
/* qsort comparison function for Datums that are OIDs */
static int
enum_elem_cmp(const void *left, const void *right)
{
Oid l = DatumGetObjectId(*((const Datum *) left));
Oid r = DatumGetObjectId(*((const Datum *) right));
if (l < r)
return -1;
if (l > r)
return 1;
return 0;
}

View File

@ -42,22 +42,44 @@
*/
#include "postgres.h"
#include <limits.h>
#include "access/hash.h"
#include "access/heapam.h"
#include "access/nbtree.h"
#include "catalog/indexing.h"
#include "catalog/pg_enum.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/inval.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/snapmgr.h"
#include "utils/syscache.h"
#include "utils/tqual.h"
#include "utils/typcache.h"
/* The main type cache hashtable searched by lookup_type_cache */
static HTAB *TypeCacheHash = NULL;
/* Private information to support comparisons of enum values */
typedef struct
{
Oid enum_oid; /* OID of one enum value */
float4 sort_order; /* its sort position */
} EnumItem;
typedef struct TypeCacheEnumData
{
Oid bitmap_base; /* OID corresponding to bit 0 of bitmapset */
Bitmapset *sorted_values; /* Set of OIDs known to be in order */
int num_values; /* total number of values in enum */
EnumItem enum_values[1]; /* VARIABLE LENGTH ARRAY */
} TypeCacheEnumData;
/*
* We use a separate table for storing the definitions of non-anonymous
* record types. Once defined, a record type will be remembered for the
@ -88,6 +110,9 @@ static int32 RecordCacheArrayLen = 0; /* allocated length of array */
static int32 NextRecordTypmod = 0; /* number of entries used */
static void TypeCacheRelCallback(Datum arg, Oid relid);
static void load_enum_cache_data(TypeCacheEntry *tcache);
static EnumItem *find_enumitem(TypeCacheEnumData *enumdata, Oid arg);
static int enum_oid_cmp(const void *left, const void *right);
/*
@ -551,3 +576,300 @@ TypeCacheRelCallback(Datum arg, Oid relid)
}
}
}
/*
* Check if given OID is part of the subset that's sortable by comparisons
*/
static inline bool
enum_known_sorted(TypeCacheEnumData *enumdata, Oid arg)
{
Oid offset;
if (arg < enumdata->bitmap_base)
return false;
offset = arg - enumdata->bitmap_base;
if (offset > (Oid) INT_MAX)
return false;
return bms_is_member((int) offset, enumdata->sorted_values);
}
/*
* compare_values_of_enum
* Compare two members of an enum type.
* Return <0, 0, or >0 according as arg1 <, =, or > arg2.
*
* Note: currently, the enumData cache is refreshed only if we are asked
* to compare an enum value that is not already in the cache. This is okay
* because there is no support for re-ordering existing values, so comparisons
* of previously cached values will return the right answer even if other
* values have been added since we last loaded the cache.
*
* Note: the enum logic has a special-case rule about even-numbered versus
* odd-numbered OIDs, but we take no account of that rule here; this
* routine shouldn't even get called when that rule applies.
*/
int
compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2)
{
TypeCacheEnumData *enumdata;
EnumItem *item1;
EnumItem *item2;
/*
* Equal OIDs are certainly equal --- this case was probably handled
* by our caller, but we may as well check.
*/
if (arg1 == arg2)
return 0;
/* Load up the cache if first time through */
if (tcache->enumData == NULL)
load_enum_cache_data(tcache);
enumdata = tcache->enumData;
/*
* If both OIDs are known-sorted, we can just compare them directly.
*/
if (enum_known_sorted(enumdata, arg1) &&
enum_known_sorted(enumdata, arg2))
{
if (arg1 < arg2)
return -1;
else
return 1;
}
/*
* Slow path: we have to identify their actual sort-order positions.
*/
item1 = find_enumitem(enumdata, arg1);
item2 = find_enumitem(enumdata, arg2);
if (item1 == NULL || item2 == NULL)
{
/*
* We couldn't find one or both values. That means the enum has
* changed under us, so re-initialize the cache and try again.
* We don't bother retrying the known-sorted case in this path.
*/
load_enum_cache_data(tcache);
enumdata = tcache->enumData;
item1 = find_enumitem(enumdata, arg1);
item2 = find_enumitem(enumdata, arg2);
/*
* If we still can't find the values, complain: we must have
* corrupt data.
*/
if (item1 == NULL)
elog(ERROR, "enum value %u not found in cache for enum %s",
arg1, format_type_be(tcache->type_id));
if (item2 == NULL)
elog(ERROR, "enum value %u not found in cache for enum %s",
arg2, format_type_be(tcache->type_id));
}
if (item1->sort_order < item2->sort_order)
return -1;
else if (item1->sort_order > item2->sort_order)
return 1;
else
return 0;
}
/*
* Load (or re-load) the enumData member of the typcache entry.
*/
static void
load_enum_cache_data(TypeCacheEntry *tcache)
{
TypeCacheEnumData *enumdata;
Relation enum_rel;
SysScanDesc enum_scan;
HeapTuple enum_tuple;
ScanKeyData skey;
EnumItem *items;
int numitems;
int maxitems;
Oid bitmap_base;
Bitmapset *bitmap;
MemoryContext oldcxt;
int bm_size,
start_pos;
/* Check that this is actually an enum */
if (tcache->typtype != TYPTYPE_ENUM)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("%s is not an enum",
format_type_be(tcache->type_id))));
/*
* Read all the information for members of the enum type. We collect
* the info in working memory in the caller's context, and then transfer
* it to permanent memory in CacheMemoryContext. This minimizes the risk
* of leaking memory from CacheMemoryContext in the event of an error
* partway through.
*/
maxitems = 64;
items = (EnumItem *) palloc(sizeof(EnumItem) * maxitems);
numitems = 0;
/*
* Scan pg_enum for the members of the target enum type. We use a
* current MVCC snapshot, *not* SnapshotNow, so that we see a consistent
* set of rows even if someone commits a renumbering of the enum meanwhile.
* See comments for RenumberEnumType in catalog/pg_enum.c for more info.
*/
ScanKeyInit(&skey,
Anum_pg_enum_enumtypid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(tcache->type_id));
enum_rel = heap_open(EnumRelationId, AccessShareLock);
enum_scan = systable_beginscan(enum_rel,
EnumTypIdLabelIndexId,
true, GetTransactionSnapshot(),
1, &skey);
while (HeapTupleIsValid(enum_tuple = systable_getnext(enum_scan)))
{
Form_pg_enum en = (Form_pg_enum) GETSTRUCT(enum_tuple);
if (numitems >= maxitems)
{
maxitems *= 2;
items = (EnumItem *) repalloc(items, sizeof(EnumItem) * maxitems);
}
items[numitems].enum_oid = HeapTupleGetOid(enum_tuple);
items[numitems].sort_order = en->enumsortorder;
numitems++;
}
systable_endscan(enum_scan);
heap_close(enum_rel, AccessShareLock);
/* Sort the items into OID order */
qsort(items, numitems, sizeof(EnumItem), enum_oid_cmp);
/*
* Here, we create a bitmap listing a subset of the enum's OIDs that are
* known to be in order and can thus be compared with just OID comparison.
*
* The point of this is that the enum's initial OIDs were certainly in
* order, so there is some subset that can be compared via OID comparison;
* and we'd rather not do binary searches unnecessarily.
*
* This is somewhat heuristic, and might identify a subset of OIDs that
* isn't exactly what the type started with. That's okay as long as
* the subset is correctly sorted.
*/
bitmap_base = InvalidOid;
bitmap = NULL;
bm_size = 1; /* only save sets of at least 2 OIDs */
for (start_pos = 0; start_pos < numitems - 1; start_pos++)
{
/*
* Identify longest sorted subsequence starting at start_pos
*/
Bitmapset *this_bitmap = bms_make_singleton(0);
int this_bm_size = 1;
Oid start_oid = items[start_pos].enum_oid;
float4 prev_order = items[start_pos].sort_order;
int i;
for (i = start_pos + 1; i < numitems; i++)
{
Oid offset;
offset = items[i].enum_oid - start_oid;
/* quit if bitmap would be too large; cutoff is arbitrary */
if (offset >= 8192)
break;
/* include the item if it's in-order */
if (items[i].sort_order > prev_order)
{
prev_order = items[i].sort_order;
this_bitmap = bms_add_member(this_bitmap, (int) offset);
this_bm_size++;
}
}
/* Remember it if larger than previous best */
if (this_bm_size > bm_size)
{
bms_free(bitmap);
bitmap_base = start_oid;
bitmap = this_bitmap;
bm_size = this_bm_size;
}
else
bms_free(this_bitmap);
/*
* Done if it's not possible to find a longer sequence in the rest
* of the list. In typical cases this will happen on the first
* iteration, which is why we create the bitmaps on the fly instead
* of doing a second pass over the list.
*/
if (bm_size >= (numitems - start_pos - 1))
break;
}
/* OK, copy the data into CacheMemoryContext */
oldcxt = MemoryContextSwitchTo(CacheMemoryContext);
enumdata = (TypeCacheEnumData *)
palloc(offsetof(TypeCacheEnumData, enum_values) +
numitems * sizeof(EnumItem));
enumdata->bitmap_base = bitmap_base;
enumdata->sorted_values = bms_copy(bitmap);
enumdata->num_values = numitems;
memcpy(enumdata->enum_values, items, numitems * sizeof(EnumItem));
MemoryContextSwitchTo(oldcxt);
pfree(items);
bms_free(bitmap);
/* And link the finished cache struct into the typcache */
if (tcache->enumData != NULL)
pfree(tcache->enumData);
tcache->enumData = enumdata;
}
/*
* Locate the EnumItem with the given OID, if present
*/
static EnumItem *
find_enumitem(TypeCacheEnumData *enumdata, Oid arg)
{
EnumItem srch;
/* On some versions of Solaris, bsearch of zero items dumps core */
if (enumdata->num_values <= 0)
return NULL;
srch.enum_oid = arg;
return bsearch(&srch, enumdata->enum_values, enumdata->num_values,
sizeof(EnumItem), enum_oid_cmp);
}
/*
* qsort comparison function for OID-ordered EnumItems
*/
static int
enum_oid_cmp(const void *left, const void *right)
{
const EnumItem *l = (const EnumItem *) left;
const EnumItem *r = (const EnumItem *) right;
if (l->enum_oid < r->enum_oid)
return -1;
else if (l->enum_oid > r->enum_oid)
return 1;
else
return 0;
}

View File

@ -6657,14 +6657,21 @@ dumpEnumType(Archive *fout, TypeInfo *tyinfo)
Oid enum_oid;
char *label;
/* Set proper schema search path so regproc references list correctly */
selectSourceSchema(tyinfo->dobj.namespace->dobj.name);
/* Set proper schema search path */
selectSourceSchema("pg_catalog");
appendPQExpBuffer(query, "SELECT oid, enumlabel "
"FROM pg_catalog.pg_enum "
"WHERE enumtypid = '%u'"
"ORDER BY oid",
tyinfo->dobj.catId.oid);
if (fout->remoteVersion >= 90100)
appendPQExpBuffer(query, "SELECT oid, enumlabel "
"FROM pg_catalog.pg_enum "
"WHERE enumtypid = '%u'"
"ORDER BY enumsortorder",
tyinfo->dobj.catId.oid);
else
appendPQExpBuffer(query, "SELECT oid, enumlabel "
"FROM pg_catalog.pg_enum "
"WHERE enumtypid = '%u'"
"ORDER BY oid",
tyinfo->dobj.catId.oid);
res = PQexec(g_conn, query->data);
check_sql_result(res, g_conn, query->data, PGRES_TUPLES_OK);
@ -6713,13 +6720,15 @@ dumpEnumType(Archive *fout, TypeInfo *tyinfo)
if (i == 0)
appendPQExpBuffer(q, "\n-- For binary upgrade, must preserve pg_enum oids\n");
appendPQExpBuffer(q,
"SELECT binary_upgrade.add_pg_enum_label('%u'::pg_catalog.oid, "
"'%u'::pg_catalog.oid, ",
enum_oid, tyinfo->dobj.catId.oid);
"SELECT binary_upgrade.set_next_pg_enum_oid('%u'::pg_catalog.oid);\n",
enum_oid);
appendPQExpBuffer(q, "ALTER TYPE %s.",
fmtId(tyinfo->dobj.namespace->dobj.name));
appendPQExpBuffer(q, "%s ADD ",
fmtId(tyinfo->dobj.name));
appendStringLiteralAH(q, label, fout);
appendPQExpBuffer(q, ");\n");
appendPQExpBuffer(q, ";\n\n");
}
appendPQExpBuffer(q, "\n");
}
ArchiveEntry(fout, tyinfo->dobj.catId, tyinfo->dobj.dumpId,

View File

@ -473,17 +473,27 @@ describeTypes(const char *pattern, bool verbose, bool showSystem)
gettext_noop("Internal name"),
gettext_noop("Size"));
if (verbose && pset.sversion >= 80300)
{
appendPQExpBuffer(&buf,
" pg_catalog.array_to_string(\n"
" ARRAY(\n"
" SELECT e.enumlabel\n"
" FROM pg_catalog.pg_enum e\n"
" WHERE e.enumtypid = t.oid\n"
" ORDER BY e.oid\n"
" WHERE e.enumtypid = t.oid\n");
if (pset.sversion >= 90100)
appendPQExpBuffer(&buf,
" ORDER BY e.enumsortorder\n");
else
appendPQExpBuffer(&buf,
" ORDER BY e.oid\n");
appendPQExpBuffer(&buf,
" ),\n"
" E'\\n'\n"
" ) AS \"%s\",\n",
gettext_noop("Elements"));
}
appendPQExpBuffer(&buf,
" pg_catalog.obj_description(t.oid, 'pg_type') as \"%s\"\n",

View File

@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 201010201
#define CATALOG_VERSION_NO 201010241
#endif

View File

@ -147,6 +147,8 @@ DECLARE_UNIQUE_INDEX(pg_enum_oid_index, 3502, on pg_enum using btree(oid oid_ops
#define EnumOidIndexId 3502
DECLARE_UNIQUE_INDEX(pg_enum_typid_label_index, 3503, on pg_enum using btree(enumtypid oid_ops, enumlabel name_ops));
#define EnumTypIdLabelIndexId 3503
DECLARE_UNIQUE_INDEX(pg_enum_typid_sortorder_index, 3534, on pg_enum using btree(enumtypid oid_ops, enumsortorder float4_ops));
#define EnumTypIdSortOrderIndexId 3534
/* This following index is not used for a cache and is not unique */
DECLARE_INDEX(pg_index_indrelid_index, 2678, on pg_index using btree(indrelid oid_ops));

View File

@ -34,6 +34,7 @@
CATALOG(pg_enum,3501)
{
Oid enumtypid; /* OID of owning enum type */
float4 enumsortorder; /* sort position of this enum value */
NameData enumlabel; /* text representation of enum value */
} FormData_pg_enum;
@ -48,9 +49,10 @@ typedef FormData_pg_enum *Form_pg_enum;
* compiler constants for pg_enum
* ----------------
*/
#define Natts_pg_enum 2
#define Natts_pg_enum 3
#define Anum_pg_enum_enumtypid 1
#define Anum_pg_enum_enumlabel 2
#define Anum_pg_enum_enumsortorder 2
#define Anum_pg_enum_enumlabel 3
/* ----------------
* pg_enum has no initial contents
@ -60,8 +62,9 @@ typedef FormData_pg_enum *Form_pg_enum;
/*
* prototypes for functions in pg_enum.c
*/
extern void EnumValuesCreate(Oid enumTypeOid, List *vals,
Oid binary_upgrade_next_pg_enum_oid);
extern void EnumValuesCreate(Oid enumTypeOid, List *vals);
extern void EnumValuesDelete(Oid enumTypeOid);
extern void AddEnumLabel(Oid enumTypeOid, const char *newVal,
const char *neighbor, bool newValIsAfter);
#endif /* PG_ENUM_H */

View File

@ -24,6 +24,7 @@ extern void RemoveTypes(DropStmt *drop);
extern void RemoveTypeById(Oid typeOid);
extern void DefineDomain(CreateDomainStmt *stmt);
extern void DefineEnum(CreateEnumStmt *stmt);
extern void AlterEnum(AlterEnumStmt *stmt);
extern Oid DefineCompositeType(const RangeVar *typevar, List *coldeflist);
extern Oid AssignTypeArrayOid(void);

View File

@ -338,6 +338,7 @@ typedef enum NodeTag
T_ReassignOwnedStmt,
T_CompositeTypeStmt,
T_CreateEnumStmt,
T_AlterEnumStmt,
T_AlterTSDictionaryStmt,
T_AlterTSConfigurationStmt,
T_CreateFdwStmt,

View File

@ -2193,6 +2193,18 @@ typedef struct CreateEnumStmt
List *vals; /* enum values (list of Value strings) */
} CreateEnumStmt;
/* ----------------------
* Alter Type Statement, enum types
* ----------------------
*/
typedef struct AlterEnumStmt
{
NodeTag type;
List *typeName; /* qualified name (list of Value strings) */
char *newVal; /* new enum value's name */
char *newValNeighbor; /* neighboring enum value, if specified */
bool newValIsAfter; /* place new enum value after neighbor? */
} AlterEnumStmt;
/* ----------------------
* Create View Statement

View File

@ -20,6 +20,9 @@
#include "fmgr.h"
/* TypeCacheEnumData is an opaque struct known only within typcache.c */
struct TypeCacheEnumData;
typedef struct TypeCacheEntry
{
/* typeId is the hash lookup key and MUST BE FIRST */
@ -63,6 +66,12 @@ typedef struct TypeCacheEntry
* reference-counted tupledesc.)
*/
TupleDesc tupDesc;
/*
* Private information about an enum type. NULL if not enum or
* information hasn't been requested.
*/
struct TypeCacheEnumData *enumData;
} TypeCacheEntry;
/* Bit flags to indicate which fields a given caller needs to have set */
@ -86,4 +95,6 @@ extern TupleDesc lookup_rowtype_tupdesc_copy(Oid type_id, int32 typmod);
extern void assign_record_type_typmod(TupleDesc tupDesc);
extern int compare_values_of_enum(TypeCacheEntry *tcache, Oid arg1, Oid arg2);
#endif /* TYPCACHE_H */

View File

@ -24,6 +24,155 @@ SELECT 'mauve'::rainbow;
ERROR: invalid input value for enum rainbow: "mauve"
LINE 1: SELECT 'mauve'::rainbow;
^
--
-- adding new values
--
CREATE TYPE planets AS ENUM ( 'venus', 'earth', 'mars' );
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
enumlabel | enumsortorder
-----------+---------------
venus | 1
earth | 2
mars | 3
(3 rows)
ALTER TYPE planets ADD 'uranus';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
enumlabel | enumsortorder
-----------+---------------
venus | 1
earth | 2
mars | 3
uranus | 4
(4 rows)
ALTER TYPE planets ADD 'mercury' BEFORE 'venus';
ALTER TYPE planets ADD 'saturn' BEFORE 'uranus';
ALTER TYPE planets ADD 'jupiter' AFTER 'mars';
ALTER TYPE planets ADD 'neptune' AFTER 'uranus';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
enumlabel | enumsortorder
-----------+---------------
mercury | 0
venus | 1
earth | 2
mars | 3
jupiter | 3.25
saturn | 3.5
uranus | 4
neptune | 5
(8 rows)
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY enumlabel::planets;
enumlabel | enumsortorder
-----------+---------------
mercury | 0
venus | 1
earth | 2
mars | 3
jupiter | 3.25
saturn | 3.5
uranus | 4
neptune | 5
(8 rows)
-- errors for adding labels
ALTER TYPE planets ADD
'plutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutopluto';
ERROR: invalid enum label "plutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutopluto"
DETAIL: Labels must be 63 characters or less.
ALTER TYPE planets ADD 'pluto' AFTER 'zeus';
ERROR: "zeus" is not an existing enum label
--
-- Test inserting so many values that we have to renumber
--
create type insenum as enum ('L1', 'L2');
alter type insenum add 'i1' before 'L2';
alter type insenum add 'i2' before 'L2';
alter type insenum add 'i3' before 'L2';
alter type insenum add 'i4' before 'L2';
alter type insenum add 'i5' before 'L2';
alter type insenum add 'i6' before 'L2';
alter type insenum add 'i7' before 'L2';
alter type insenum add 'i8' before 'L2';
alter type insenum add 'i9' before 'L2';
alter type insenum add 'i10' before 'L2';
alter type insenum add 'i11' before 'L2';
alter type insenum add 'i12' before 'L2';
alter type insenum add 'i13' before 'L2';
alter type insenum add 'i14' before 'L2';
alter type insenum add 'i15' before 'L2';
alter type insenum add 'i16' before 'L2';
alter type insenum add 'i17' before 'L2';
alter type insenum add 'i18' before 'L2';
alter type insenum add 'i19' before 'L2';
alter type insenum add 'i20' before 'L2';
alter type insenum add 'i21' before 'L2';
alter type insenum add 'i22' before 'L2';
alter type insenum add 'i23' before 'L2';
alter type insenum add 'i24' before 'L2';
alter type insenum add 'i25' before 'L2';
alter type insenum add 'i26' before 'L2';
alter type insenum add 'i27' before 'L2';
alter type insenum add 'i28' before 'L2';
alter type insenum add 'i29' before 'L2';
alter type insenum add 'i30' before 'L2';
-- The exact values of enumsortorder will now depend on the local properties
-- of float4, but in any reasonable implementation we should get at least
-- 20 splits before having to renumber; so only hide values > 20.
SELECT enumlabel,
case when enumsortorder > 20 then null else enumsortorder end as so
FROM pg_enum
WHERE enumtypid = 'insenum'::regtype
ORDER BY enumsortorder;
enumlabel | so
-----------+----
L1 | 1
i1 | 2
i2 | 3
i3 | 4
i4 | 5
i5 | 6
i6 | 7
i7 | 8
i8 | 9
i9 | 10
i10 | 11
i11 | 12
i12 | 13
i13 | 14
i14 | 15
i15 | 16
i16 | 17
i17 | 18
i18 | 19
i19 | 20
i20 |
i21 |
i22 |
i23 |
i24 |
i25 |
i26 |
i27 |
i28 |
i29 |
i30 |
L2 |
(32 rows)
--
-- Basic table creation, row selection
--
@ -403,7 +552,7 @@ SELECT COUNT(*) FROM pg_type WHERE typname = 'rainbow';
SELECT * FROM pg_enum WHERE NOT EXISTS
(SELECT 1 FROM pg_type WHERE pg_type.oid = enumtypid);
enumtypid | enumlabel
-----------+-----------
enumtypid | enumsortorder | enumlabel
-----------+---------------+-----------
(0 rows)

View File

@ -15,6 +15,92 @@ SELECT COUNT(*) FROM pg_enum WHERE enumtypid = 'rainbow'::regtype;
SELECT 'red'::rainbow;
SELECT 'mauve'::rainbow;
--
-- adding new values
--
CREATE TYPE planets AS ENUM ( 'venus', 'earth', 'mars' );
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
ALTER TYPE planets ADD 'uranus';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
ALTER TYPE planets ADD 'mercury' BEFORE 'venus';
ALTER TYPE planets ADD 'saturn' BEFORE 'uranus';
ALTER TYPE planets ADD 'jupiter' AFTER 'mars';
ALTER TYPE planets ADD 'neptune' AFTER 'uranus';
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY 2;
SELECT enumlabel, enumsortorder
FROM pg_enum
WHERE enumtypid = 'planets'::regtype
ORDER BY enumlabel::planets;
-- errors for adding labels
ALTER TYPE planets ADD
'plutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutoplutopluto';
ALTER TYPE planets ADD 'pluto' AFTER 'zeus';
--
-- Test inserting so many values that we have to renumber
--
create type insenum as enum ('L1', 'L2');
alter type insenum add 'i1' before 'L2';
alter type insenum add 'i2' before 'L2';
alter type insenum add 'i3' before 'L2';
alter type insenum add 'i4' before 'L2';
alter type insenum add 'i5' before 'L2';
alter type insenum add 'i6' before 'L2';
alter type insenum add 'i7' before 'L2';
alter type insenum add 'i8' before 'L2';
alter type insenum add 'i9' before 'L2';
alter type insenum add 'i10' before 'L2';
alter type insenum add 'i11' before 'L2';
alter type insenum add 'i12' before 'L2';
alter type insenum add 'i13' before 'L2';
alter type insenum add 'i14' before 'L2';
alter type insenum add 'i15' before 'L2';
alter type insenum add 'i16' before 'L2';
alter type insenum add 'i17' before 'L2';
alter type insenum add 'i18' before 'L2';
alter type insenum add 'i19' before 'L2';
alter type insenum add 'i20' before 'L2';
alter type insenum add 'i21' before 'L2';
alter type insenum add 'i22' before 'L2';
alter type insenum add 'i23' before 'L2';
alter type insenum add 'i24' before 'L2';
alter type insenum add 'i25' before 'L2';
alter type insenum add 'i26' before 'L2';
alter type insenum add 'i27' before 'L2';
alter type insenum add 'i28' before 'L2';
alter type insenum add 'i29' before 'L2';
alter type insenum add 'i30' before 'L2';
-- The exact values of enumsortorder will now depend on the local properties
-- of float4, but in any reasonable implementation we should get at least
-- 20 splits before having to renumber; so only hide values > 20.
SELECT enumlabel,
case when enumsortorder > 20 then null else enumsortorder end as so
FROM pg_enum
WHERE enumtypid = 'insenum'::regtype
ORDER BY enumsortorder;
--
-- Basic table creation, row selection
--