205 lines
7.8 KiB
C
205 lines
7.8 KiB
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* vacuum.h
|
|
* header file for postgres vacuum cleaner and statistics analyzer
|
|
*
|
|
*
|
|
* Portions Copyright (c) 1996-2018, PostgreSQL Global Development Group
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
*
|
|
* src/include/commands/vacuum.h
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
#ifndef VACUUM_H
|
|
#define VACUUM_H
|
|
|
|
#include "access/htup.h"
|
|
#include "catalog/pg_statistic.h"
|
|
#include "catalog/pg_type.h"
|
|
#include "nodes/parsenodes.h"
|
|
#include "storage/buf.h"
|
|
#include "storage/lock.h"
|
|
#include "utils/relcache.h"
|
|
|
|
|
|
/*----------
|
|
* ANALYZE builds one of these structs for each attribute (column) that is
|
|
* to be analyzed. The struct and subsidiary data are in anl_context,
|
|
* so they live until the end of the ANALYZE operation.
|
|
*
|
|
* The type-specific typanalyze function is passed a pointer to this struct
|
|
* and must return true to continue analysis, false to skip analysis of this
|
|
* column. In the true case it must set the compute_stats and minrows fields,
|
|
* and can optionally set extra_data to pass additional info to compute_stats.
|
|
* minrows is its request for the minimum number of sample rows to be gathered
|
|
* (but note this request might not be honored, eg if there are fewer rows
|
|
* than that in the table).
|
|
*
|
|
* The compute_stats routine will be called after sample rows have been
|
|
* gathered. Aside from this struct, it is passed:
|
|
* fetchfunc: a function for accessing the column values from the
|
|
* sample rows
|
|
* samplerows: the number of sample tuples
|
|
* totalrows: estimated total number of rows in relation
|
|
* The fetchfunc may be called with rownum running from 0 to samplerows-1.
|
|
* It returns a Datum and an isNull flag.
|
|
*
|
|
* compute_stats should set stats_valid true if it is able to compute
|
|
* any useful statistics. If it does, the remainder of the struct holds
|
|
* the information to be stored in a pg_statistic row for the column. Be
|
|
* careful to allocate any pointed-to data in anl_context, which will NOT
|
|
* be CurrentMemoryContext when compute_stats is called.
|
|
*
|
|
* Note: for the moment, all comparisons done for statistical purposes
|
|
* should use the database's default collation (DEFAULT_COLLATION_OID).
|
|
* This might change in some future release.
|
|
*----------
|
|
*/
|
|
typedef struct VacAttrStats *VacAttrStatsP;
|
|
|
|
typedef Datum (*AnalyzeAttrFetchFunc) (VacAttrStatsP stats, int rownum,
|
|
bool *isNull);
|
|
|
|
typedef void (*AnalyzeAttrComputeStatsFunc) (VacAttrStatsP stats,
|
|
AnalyzeAttrFetchFunc fetchfunc,
|
|
int samplerows,
|
|
double totalrows);
|
|
|
|
typedef struct VacAttrStats
|
|
{
|
|
/*
|
|
* These fields are set up by the main ANALYZE code before invoking the
|
|
* type-specific typanalyze function.
|
|
*
|
|
* Note: do not assume that the data being analyzed has the same datatype
|
|
* shown in attr, ie do not trust attr->atttypid, attlen, etc. This is
|
|
* because some index opclasses store a different type than the underlying
|
|
* column/expression. Instead use attrtypid, attrtypmod, and attrtype for
|
|
* information about the datatype being fed to the typanalyze function.
|
|
*/
|
|
Form_pg_attribute attr; /* copy of pg_attribute row for column */
|
|
Oid attrtypid; /* type of data being analyzed */
|
|
int32 attrtypmod; /* typmod of data being analyzed */
|
|
Form_pg_type attrtype; /* copy of pg_type row for attrtypid */
|
|
MemoryContext anl_context; /* where to save long-lived data */
|
|
|
|
/*
|
|
* These fields must be filled in by the typanalyze routine, unless it
|
|
* returns false.
|
|
*/
|
|
AnalyzeAttrComputeStatsFunc compute_stats; /* function pointer */
|
|
int minrows; /* Minimum # of rows wanted for stats */
|
|
void *extra_data; /* for extra type-specific data */
|
|
|
|
/*
|
|
* These fields are to be filled in by the compute_stats routine. (They
|
|
* are initialized to zero when the struct is created.)
|
|
*/
|
|
bool stats_valid;
|
|
float4 stanullfrac; /* fraction of entries that are NULL */
|
|
int32 stawidth; /* average width of column values */
|
|
float4 stadistinct; /* # distinct values */
|
|
int16 stakind[STATISTIC_NUM_SLOTS];
|
|
Oid staop[STATISTIC_NUM_SLOTS];
|
|
int numnumbers[STATISTIC_NUM_SLOTS];
|
|
float4 *stanumbers[STATISTIC_NUM_SLOTS];
|
|
int numvalues[STATISTIC_NUM_SLOTS];
|
|
Datum *stavalues[STATISTIC_NUM_SLOTS];
|
|
|
|
/*
|
|
* These fields describe the stavalues[n] element types. They will be
|
|
* initialized to match attrtypid, but a custom typanalyze function might
|
|
* want to store an array of something other than the analyzed column's
|
|
* elements. It should then overwrite these fields.
|
|
*/
|
|
Oid statypid[STATISTIC_NUM_SLOTS];
|
|
int16 statyplen[STATISTIC_NUM_SLOTS];
|
|
bool statypbyval[STATISTIC_NUM_SLOTS];
|
|
char statypalign[STATISTIC_NUM_SLOTS];
|
|
|
|
/*
|
|
* These fields are private to the main ANALYZE code and should not be
|
|
* looked at by type-specific functions.
|
|
*/
|
|
int tupattnum; /* attribute number within tuples */
|
|
HeapTuple *rows; /* access info for std fetch function */
|
|
TupleDesc tupDesc;
|
|
Datum *exprvals; /* access info for index fetch function */
|
|
bool *exprnulls;
|
|
int rowstride;
|
|
} VacAttrStats;
|
|
|
|
/*
|
|
* Parameters customizing behavior of VACUUM and ANALYZE.
|
|
*/
|
|
typedef struct VacuumParams
|
|
{
|
|
int freeze_min_age; /* min freeze age, -1 to use default */
|
|
int freeze_table_age; /* age at which to scan whole table */
|
|
int multixact_freeze_min_age; /* min multixact freeze age, -1 to
|
|
* use default */
|
|
int multixact_freeze_table_age; /* multixact age at which to scan
|
|
* whole table */
|
|
bool is_wraparound; /* force a for-wraparound vacuum */
|
|
int log_min_duration; /* minimum execution threshold in ms at
|
|
* which verbose logs are activated, -1
|
|
* to use default */
|
|
} VacuumParams;
|
|
|
|
/* GUC parameters */
|
|
extern PGDLLIMPORT int default_statistics_target; /* PGDLLIMPORT for PostGIS */
|
|
extern int vacuum_freeze_min_age;
|
|
extern int vacuum_freeze_table_age;
|
|
extern int vacuum_multixact_freeze_min_age;
|
|
extern int vacuum_multixact_freeze_table_age;
|
|
|
|
|
|
/* in commands/vacuum.c */
|
|
extern void ExecVacuum(VacuumStmt *vacstmt, bool isTopLevel);
|
|
extern void vacuum(int options, List *relations, VacuumParams *params,
|
|
BufferAccessStrategy bstrategy, bool isTopLevel);
|
|
extern void vac_open_indexes(Relation relation, LOCKMODE lockmode,
|
|
int *nindexes, Relation **Irel);
|
|
extern void vac_close_indexes(int nindexes, Relation *Irel, LOCKMODE lockmode);
|
|
extern double vac_estimate_reltuples(Relation relation,
|
|
BlockNumber total_pages,
|
|
BlockNumber scanned_pages,
|
|
double scanned_tuples);
|
|
extern void vac_update_relstats(Relation relation,
|
|
BlockNumber num_pages,
|
|
double num_tuples,
|
|
BlockNumber num_all_visible_pages,
|
|
bool hasindex,
|
|
TransactionId frozenxid,
|
|
MultiXactId minmulti,
|
|
bool in_outer_xact);
|
|
extern void vacuum_set_xid_limits(Relation rel,
|
|
int freeze_min_age, int freeze_table_age,
|
|
int multixact_freeze_min_age,
|
|
int multixact_freeze_table_age,
|
|
TransactionId *oldestXmin,
|
|
TransactionId *freezeLimit,
|
|
TransactionId *xidFullScanLimit,
|
|
MultiXactId *multiXactCutoff,
|
|
MultiXactId *mxactFullScanLimit);
|
|
extern void vac_update_datfrozenxid(void);
|
|
extern void vacuum_delay_point(void);
|
|
|
|
/* in commands/vacuumlazy.c */
|
|
extern void lazy_vacuum_rel(Relation onerel, int options,
|
|
VacuumParams *params, BufferAccessStrategy bstrategy);
|
|
|
|
/* in commands/analyze.c */
|
|
extern void analyze_rel(Oid relid, RangeVar *relation, int options,
|
|
VacuumParams *params, List *va_cols, bool in_outer_xact,
|
|
BufferAccessStrategy bstrategy);
|
|
extern bool std_typanalyze(VacAttrStats *stats);
|
|
|
|
/* in utils/misc/sampling.c --- duplicate of declarations in utils/sampling.h */
|
|
extern double anl_random_fract(void);
|
|
extern double anl_init_selection_state(int n);
|
|
extern double anl_get_next_S(double t, int n, double *stateptr);
|
|
|
|
#endif /* VACUUM_H */
|