diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 2ec9c3026c..384a71a74b 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -1,4 +1,4 @@ - + Server Configuration @@ -3279,7 +3279,8 @@ SELECT * FROM parent WHERE key = 2400; Abort any statement that takes over the specified number of - milliseconds. If log_min_error_statement is set to + milliseconds, starting from the time the command arrives at the server + from the client. If log_min_error_statement is set to ERROR or lower, the statement that timed out will also be logged. A value of zero (the default) turns off the limitation. diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 0b5fb01e4d..b53bdca6fc 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -1,4 +1,4 @@ - + Functions and Operators @@ -5302,6 +5302,15 @@ SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})'); now + + transaction_timestamp + + + statement_timestamp + + + clock_timestamp + timeofday @@ -5358,7 +5367,7 @@ SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})'); current_timestamp timestamp with time zone - Date and time; see + Date and time of start of current transaction; see @@ -5474,8 +5483,36 @@ SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})'); now() timestamp with time zone - Current date and time (equivalent to - current_timestamp); see + Date and time of start of current transaction (equivalent to + CURRENT_TIMESTAMP); see + + + + + + + transaction_timestamp() + timestamp with time zone + Date and time of start of current transaction (equivalent to + CURRENT_TIMESTAMP); see + + + + + + + statement_timestamp() + timestamp with time zone + Date and time of start of current statement; see + + + + + + + clock_timestamp() + timestamp with time zone + Current date and time (changes during statement execution); see @@ -5484,7 +5521,8 @@ SELECT SUBSTRING('XY1234Z', 'Y*?([0-9]{1,3})'); timeofday() text - Current date and time; see + Current date and time (like clock_timestamp), but as a Unix-style text value; + see @@ -6072,7 +6110,7 @@ SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT TIME ZONE 'MST'; - Current Date/Time + Date/Time of Transaction Start date @@ -6085,8 +6123,8 @@ SELECT TIMESTAMP WITH TIME ZONE '2001-02-16 20:38:40-05' AT TIME ZONE 'MST'; - The following functions are available to obtain the current date and/or - time: + The following functions are available to obtain the date and/or + time of the start of the current transaction: CURRENT_DATE CURRENT_TIME @@ -6138,12 +6176,6 @@ SELECT LOCALTIMESTAMP; - - The function now() is the traditional - PostgreSQL equivalent to - CURRENT_TIMESTAMP. - - It is important to know that CURRENT_TIMESTAMP and related functions return @@ -6152,26 +6184,31 @@ SELECT LOCALTIMESTAMP; the intent is to allow a single transaction to have a consistent notion of the current time, so that multiple modifications within the same transaction bear the same - time stamp. + time stamp. Consider using statement_timestamp or + clock_timestamp if you need something that changes + more frequently. - - - Other database systems may advance these values more - frequently. - - + + CURRENT_TIMESTAMP might not be the + transaction start time on other database systems. + For this reason, and for completeness, + transaction_timestamp is provided. + The function now() is the traditional + PostgreSQL equivalent to + the SQL-standard CURRENT_TIMESTAMP. + - There is also the function timeofday() which - returns the wall-clock time and advances during transactions. For - historical reasons timeofday() returns a - text string rather than a timestamp - value: - -SELECT timeofday(); -Result: Sat Feb 17 19:07:32.000126 2001 EST - + STATEMENT_TIMESTAMP is the time the statement + arrived at the server from the client. It is not the time + the command started execution. If multiple commands were + sent as a single query string to the server, each command + has the same STATEMENT_TIMESTAMP because they + all arrived at the same time. Also, commands executed + by server-side functions have a STATEMENT_TIMESTAMP + based on the time the client sent the query that triggered + the function, not the time the function was executed. diff --git a/src/backend/access/transam/xact.c b/src/backend/access/transam/xact.c index 0bbe2c0d49..b59cea044b 100644 --- a/src/backend/access/transam/xact.c +++ b/src/backend/access/transam/xact.c @@ -10,7 +10,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.219 2006/03/29 21:17:37 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/transam/xact.c,v 1.220 2006/04/25 00:25:17 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -172,6 +172,7 @@ static CommandId currentCommandId; * keep it inside the TransactionState stack. */ static TimestampTz xactStartTimestamp; +static TimestampTz stmtStartTimestamp; /* * GID to be used for preparing the current transaction. This is also @@ -427,6 +428,24 @@ GetCurrentTransactionStartTimestamp(void) return xactStartTimestamp; } +/* + * GetCurrentStatementStartTimestamp + */ +TimestampTz +GetCurrentStatementStartTimestamp(void) +{ + return stmtStartTimestamp; +} + +/* + * SetCurrentStatementStartTimestamp + */ +void +SetCurrentStatementStartTimestamp(void) +{ + stmtStartTimestamp = GetCurrentTimestamp(); +} + /* * GetCurrentTransactionNestLevel * @@ -1367,9 +1386,9 @@ StartTransaction(void) XactLockTableInsert(s->transactionId); /* - * set now() + * now() and statement_timestamp() should be the same time */ - xactStartTimestamp = GetCurrentTimestamp(); + xactStartTimestamp = stmtStartTimestamp; /* * initialize current transaction state fields diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index 04e432594e..2135c92fd8 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.485 2006/04/22 01:26:00 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/tcop/postgres.c,v 1.486 2006/04/25 00:25:18 momjian Exp $ * * NOTES * this is the "main" module of the postgres backend and @@ -118,6 +118,12 @@ static volatile sig_atomic_t got_SIGHUP = false; */ static bool xact_started = false; +/* + * Flag to keep track of whether we have done statement initialization. + * For extended query protocol this has to be remembered across messages. + */ +static bool command_initialized = false; + /* * Flag to indicate that we are doing the outer loop's read-from-client, * as opposed to any random read from client that might happen within @@ -164,6 +170,8 @@ static int ReadCommand(StringInfo inBuf); static bool log_after_parse(List *raw_parsetree_list, const char *query_string, char **prepare_string); static List *pg_rewrite_queries(List *querytree_list); +static void initialize_command(void); +static void finalize_command(void); static void start_xact_command(void); static void finish_xact_command(void); static bool IsTransactionExitStmt(Node *parsetree); @@ -858,7 +866,7 @@ exec_simple_query(const char *query_string) * one of those, else bad things will happen in xact.c. (Note that this * will normally change current memory context.) */ - start_xact_command(); + initialize_command(); /* * Zap any pre-existing unnamed statement. (While not strictly necessary, @@ -1067,7 +1075,7 @@ exec_simple_query(const char *query_string) /* * Close down transaction statement, if one is open. */ - finish_xact_command(); + finalize_command(); /* * If there were no parsetrees, return EmptyQueryResponse message. @@ -1170,7 +1178,7 @@ exec_parse_message(const char *query_string, /* string to execute */ * that this will normally change current memory context.) Nothing happens * if we are already in one. */ - start_xact_command(); + initialize_command(); /* * Switch to appropriate context for constructing parsetrees. @@ -1393,7 +1401,7 @@ exec_bind_message(StringInfo input_message) * this will normally change current memory context.) Nothing happens if * we are already in one. */ - start_xact_command(); + initialize_command(); /* Switch back to message context */ MemoryContextSwitchTo(MessageContext); @@ -1759,7 +1767,7 @@ exec_execute_message(const char *portal_name, long max_rows) * Ensure we are in a transaction command (this should normally be the * case already due to prior BIND). */ - start_xact_command(); + initialize_command(); /* * If we are in aborted transaction state, the only portals we can @@ -1883,7 +1891,7 @@ exec_describe_statement_message(const char *stmt_name) * Start up a transaction command. (Note that this will normally change * current memory context.) Nothing happens if we are already in one. */ - start_xact_command(); + initialize_command(); /* Switch back to message context */ MemoryContextSwitchTo(MessageContext); @@ -1961,7 +1969,7 @@ exec_describe_portal_message(const char *portal_name) * Start up a transaction command. (Note that this will normally change * current memory context.) Nothing happens if we are already in one. */ - start_xact_command(); + initialize_command(); /* Switch back to message context */ MemoryContextSwitchTo(MessageContext); @@ -2000,7 +2008,44 @@ exec_describe_portal_message(const char *portal_name) /* - * Convenience routines for starting/committing a single command. + * Start xact if necessary, and set statement_timestamp() and optionally + * statement_timeout. + */ +static void +initialize_command(void) +{ + if (!command_initialized) + { + SetCurrentStatementStartTimestamp(); + + /* Set statement timeout running, if any */ + if (StatementTimeout > 0) + enable_sig_alarm(StatementTimeout, true); + else + cancel_from_timeout = false; + + command_initialized = true; + } + start_xact_command(); +} + +static void +finalize_command(void) +{ + if (command_initialized) + { + /* Cancel any active statement timeout before committing */ + disable_sig_alarm(true); + + command_initialized = false; + } + finish_xact_command(); +} + + +/* + * Check if the newly-arrived query string needs to have an implicit + * transaction started. */ static void start_xact_command(void) @@ -2009,13 +2054,8 @@ start_xact_command(void) { ereport(DEBUG3, (errmsg_internal("StartTransactionCommand"))); - StartTransactionCommand(); - /* Set statement timeout running, if any */ - if (StatementTimeout > 0) - enable_sig_alarm(StatementTimeout, true); - else - cancel_from_timeout = false; + StartTransactionCommand(); xact_started = true; } @@ -2026,10 +2066,6 @@ finish_xact_command(void) { if (xact_started) { - /* Cancel any active statement timeout before committing */ - disable_sig_alarm(true); - - /* Now commit the command */ ereport(DEBUG3, (errmsg_internal("CommitTransactionCommand"))); @@ -3137,7 +3173,8 @@ PostgresMain(int argc, char *argv[], const char *username) /* We don't have a transaction command open anymore */ xact_started = false; - + command_initialized = false; + /* Now we can allow interrupts again */ RESUME_INTERRUPTS(); } @@ -3305,7 +3342,7 @@ PostgresMain(int argc, char *argv[], const char *username) pgstat_report_activity(" function call"); /* start an xact for this function invocation */ - start_xact_command(); + initialize_command(); /* switch back to message context */ MemoryContextSwitchTo(MessageContext); @@ -3328,7 +3365,7 @@ PostgresMain(int argc, char *argv[], const char *username) } /* commit the function-invocation transaction */ - finish_xact_command(); + finalize_command(); send_ready_for_query = true; break; @@ -3416,7 +3453,7 @@ PostgresMain(int argc, char *argv[], const char *username) case 'S': /* sync */ pq_getmsgend(&input_message); - finish_xact_command(); + finalize_command(); send_ready_for_query = true; break; diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c index 0524bf1239..fd40c1ebfd 100644 --- a/src/backend/utils/adt/timestamp.c +++ b/src/backend/utils/adt/timestamp.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.162 2006/03/06 22:49:16 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.163 2006/04/25 00:25:18 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -919,6 +919,18 @@ now(PG_FUNCTION_ARGS) PG_RETURN_TIMESTAMPTZ(GetCurrentTransactionStartTimestamp()); } +Datum +statement_timestamp(PG_FUNCTION_ARGS) +{ + PG_RETURN_TIMESTAMPTZ(GetCurrentStatementStartTimestamp()); +} + +Datum +clock_timestamp(PG_FUNCTION_ARGS) +{ + PG_RETURN_TIMESTAMPTZ(GetCurrentTimestamp()); +} + Datum pgsql_postmaster_start_time(PG_FUNCTION_ARGS) { diff --git a/src/include/access/xact.h b/src/include/access/xact.h index da2455f68f..6591ba0456 100644 --- a/src/include/access/xact.h +++ b/src/include/access/xact.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/access/xact.h,v 1.81 2006/03/24 04:32:13 tgl Exp $ + * $PostgreSQL: pgsql/src/include/access/xact.h,v 1.82 2006/04/25 00:25:19 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -141,6 +141,8 @@ extern TransactionId GetCurrentTransactionIdIfAny(void); extern SubTransactionId GetCurrentSubTransactionId(void); extern CommandId GetCurrentCommandId(void); extern TimestampTz GetCurrentTransactionStartTimestamp(void); +extern TimestampTz GetCurrentStatementStartTimestamp(void); +extern void SetCurrentStatementStartTimestamp(void); extern int GetCurrentTransactionNestLevel(void); extern bool TransactionIdIsCurrentTransactionId(TransactionId xid); extern void CommandCounterIncrement(void); diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h index a88d3cfd59..11b02f691a 100644 --- a/src/include/catalog/catversion.h +++ b/src/include/catalog/catversion.h @@ -37,7 +37,7 @@ * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.323 2006/04/22 01:26:01 tgl Exp $ + * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.324 2006/04/25 00:25:20 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -53,6 +53,6 @@ */ /* yyyymmddN */ -#define CATALOG_VERSION_NO 200604211 +#define CATALOG_VERSION_NO 200604241 #endif diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h index 9542d632f2..61339eadad 100644 --- a/src/include/catalog/pg_proc.h +++ b/src/include/catalog/pg_proc.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.405 2006/04/05 22:11:55 tgl Exp $ + * $PostgreSQL: pgsql/src/include/catalog/pg_proc.h,v 1.406 2006/04/25 00:25:20 momjian Exp $ * * NOTES * The script catalog/genbki.sh reads this file and generates .bki @@ -1614,6 +1614,12 @@ DATA(insert OID = 1298 ( timetzdate_pl PGNSP PGUID 14 f f t f i 2 1184 "1266 DESCR("convert time with time zone and date to timestamp with time zone"); DATA(insert OID = 1299 ( now PGNSP PGUID 12 f f t f s 0 1184 "" _null_ _null_ _null_ now - _null_ )); DESCR("current transaction time"); +DATA(insert OID = 2647 ( transaction_timestamp PGNSP PGUID 12 f f t f s 0 1184 "" _null_ _null_ _null_ now - _null_ )); +DESCR("current transaction time"); +DATA(insert OID = 2648 ( statement_timestamp PGNSP PGUID 12 f f t f s 0 1184 "" _null_ _null_ _null_ statement_timestamp - _null_ )); +DESCR("current statement time"); +DATA(insert OID = 2649 ( clock_timestamp PGNSP PGUID 12 f f t f v 0 1184 "" _null_ _null_ _null_ clock_timestamp - _null_ )); +DESCR("current clock time"); /* OIDS 1300 - 1399 */ diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h index 9747b300b6..4e9e0c3f6f 100644 --- a/src/include/utils/timestamp.h +++ b/src/include/utils/timestamp.h @@ -6,7 +6,7 @@ * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/utils/timestamp.h,v 1.59 2006/03/06 22:49:17 momjian Exp $ + * $PostgreSQL: pgsql/src/include/utils/timestamp.h,v 1.60 2006/04/25 00:25:22 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -284,6 +284,8 @@ extern Datum timestamptz_trunc(PG_FUNCTION_ARGS); extern Datum timestamptz_part(PG_FUNCTION_ARGS); extern Datum now(PG_FUNCTION_ARGS); +extern Datum statement_timestamp(PG_FUNCTION_ARGS); +extern Datum clock_timestamp(PG_FUNCTION_ARGS); extern Datum pgsql_postmaster_start_time(PG_FUNCTION_ARGS);