From 164166720d8af3930883bcccea6fea188070c3af Mon Sep 17 00:00:00 2001 From: "okbob@github.com" Date: Tue, 21 May 2024 22:40:55 +0200 Subject: [PATCH 19/19] transactional variables This commit implements transactional variables. The content of transactional session variables is sensitive to transactions and subtransactions. Any transactional variable holds a history of values necessary for revert. This history is cleaned (purged) when a) we read the variable, b) when the transaction is finished. We don't try to purge, when the last modification of a variable is from current subtransaction, or when purge was processed in current subtransaction. This patch is based on my work from Feb 2020 and it is related to discussion about features related to session variables. Now, when the all features are separated to isolated patches I can revitalize this patch, because it doesn't increase complexity of basic patches. Unlike other patches, this patch is without any review at this moment (Feb 2024), but the feature should be fully functional for people who are interested about this feature (for testing). --- doc/src/sgml/catalogs.sgml | 11 + doc/src/sgml/ref/create_variable.sgml | 10 +- src/backend/catalog/pg_variable.c | 4 + src/backend/commands/session_variable.c | 301 +++++++++++++++++- src/backend/parser/gram.y | 50 +-- src/bin/pg_dump/pg_dump.c | 10 +- src/bin/pg_dump/pg_dump.h | 1 + src/bin/pg_dump/t/002_pg_dump.pl | 36 +++ src/bin/psql/describe.c | 4 +- src/bin/psql/tab-complete.c | 5 + src/include/catalog/pg_variable.h | 3 + src/include/nodes/parsenodes.h | 1 + src/include/parser/kwlist.h | 1 + src/test/regress/expected/psql.out | 36 +-- .../regress/expected/session_variables.out | 110 ++++++- src/test/regress/sql/session_variables.sql | 58 ++++ 16 files changed, 591 insertions(+), 50 deletions(-) diff --git a/doc/src/sgml/catalogs.sgml b/doc/src/sgml/catalogs.sgml index 064cfc6cd0..2d1dcdad9f 100644 --- a/doc/src/sgml/catalogs.sgml +++ b/doc/src/sgml/catalogs.sgml @@ -9854,6 +9854,17 @@ SCRAM-SHA-256$<iteration count>:&l + + varistransact + boolean + + + True, when the variable is "transactional". In case of transaction + rollback, transactional variables are reset to their content at the + transaction start. The default value is false. + + + vareoxaction char diff --git a/doc/src/sgml/ref/create_variable.sgml b/doc/src/sgml/ref/create_variable.sgml index ef695d6637..edf01ccdf5 100644 --- a/doc/src/sgml/ref/create_variable.sgml +++ b/doc/src/sgml/ref/create_variable.sgml @@ -26,7 +26,7 @@ PostgreSQL documentation -CREATE [ { TEMPORARY | TEMP } ] [ IMMUTABLE ] VARIABLE [ IF NOT EXISTS ] name [ AS ] data_type ] [ COLLATE collation ] +CREATE [ { TEMPORARY | TEMP } ] [ { TRANSACTIONAL | TRANSACTION } ] [ IMMUTABLE ] VARIABLE [ IF NOT EXISTS ] name [ AS ] data_type ] [ COLLATE collation ] [ NOT NULL ] [ DEFAULT default_expr ] [ { ON COMMIT DROP | ON TRANSACTION END RESET } ] @@ -48,6 +48,14 @@ CREATE [ { TEMPORARY | TEMP } ] [ IMMUTABLE ] VARIABLE [ IF NOT EXISTS ] + + When a schema variable is created with a + CREATE TRANSACTIONAL VARIABLE command, the variables + content changes are transactional: in case of rollback, they are reset to + their value at the beginning of the transaction or the latest subtransaction. + The variable content is only hold in memory, and thus is not persistent. + + Session variables are retrieved by the SELECT SQL command. Their value is set with the LET SQL command. diff --git a/src/backend/catalog/pg_variable.c b/src/backend/catalog/pg_variable.c index 898c2c745e..87b246f14f 100644 --- a/src/backend/catalog/pg_variable.c +++ b/src/backend/catalog/pg_variable.c @@ -42,6 +42,7 @@ static ObjectAddress create_variable(const char *varName, bool if_not_exists, bool is_not_null, bool is_immutable, + bool is_transact, Node *varDefexpr, VariableEOXAction eoxaction); @@ -59,6 +60,7 @@ create_variable(const char *varName, bool if_not_exists, bool is_not_null, bool is_immutable, + bool is_transact, Node *varDefexpr, VariableEOXAction eoxaction) { @@ -123,6 +125,7 @@ create_variable(const char *varName, values[Anum_pg_variable_varcollation - 1] = ObjectIdGetDatum(varCollation); values[Anum_pg_variable_varisnotnull - 1] = BoolGetDatum(is_not_null); values[Anum_pg_variable_varisimmutable - 1] = BoolGetDatum(is_immutable); + values[Anum_pg_variable_varistransact - 1] = BoolGetDatum(is_transact); values[Anum_pg_variable_vareoxaction - 1] = CharGetDatum(eoxaction); if (varDefexpr) @@ -267,6 +270,7 @@ CreateVariable(ParseState *pstate, CreateSessionVarStmt *stmt) stmt->if_not_exists, stmt->is_not_null, stmt->is_immutable, + stmt->is_transact, cooked_default, stmt->eoxaction); diff --git a/src/backend/commands/session_variable.c b/src/backend/commands/session_variable.c index 21560695dc..e9494300b9 100644 --- a/src/backend/commands/session_variable.c +++ b/src/backend/commands/session_variable.c @@ -47,6 +47,19 @@ typedef struct SVariableXActDropItem SubTransactionId deleting_subid; } SVariableXActDropItem; +/* + * Used for transactional variables. Holds prev version. + */ +typedef struct PrevValue +{ + Datum value; + bool isnull; + + SubTransactionId modify_subid; + + struct PrevValue *prev_value; +} PrevValue; + /* * Values of session variables are stored in the backend local memory * inside sessionvars hash table in binary format inside a dedicated memory @@ -75,6 +88,25 @@ typedef struct SVariableData bool isnull; Datum value; + /* + * We don't need stack versions modified in same subtransaction. + * Used by transactional variables only. The value of transactional + * variable can be returned immediately when modify_subid is same + * like current subid. + */ + SubTransactionId modify_subid; + + /* + * When the modify_subid is different than current subid, then + * we need to recheck versions and throw versions related to + * reverted transactions. When purge_subid is same like current subid + * we can return the value of transaction variable without this + * recheck. + */ + SubTransactionId purge_subid; + + PrevValue *prev_value; + Oid typid; int16 typlen; bool typbyval; @@ -94,6 +126,7 @@ typedef struct SVariableData bool is_not_null; bool is_immutable; + bool is_transact; bool reset_at_eox; @@ -133,6 +166,9 @@ static bool needs_validation = false; */ static bool has_session_variables_with_reset_at_eox = false; +/* true, when transactional variables was modified */ +static bool has_modified_transactional_variables = false; + /* * The content of session variables is not removed immediately. When it * is possible we do this at the transaction end. But when the transaction failed, @@ -148,6 +184,7 @@ static List *xact_drop_items = NIL; static void register_session_variable_xact_drop(Oid varid); static void unregister_session_variable_xact_drop(Oid varid); +static bool purge_session_variable(SVariable svar); /* * Callback function for session variable invalidation. @@ -303,8 +340,25 @@ unregister_session_variable_xact_drop(Oid varid) * Release stored value, free memory */ static void -free_session_variable_value(SVariable svar) +free_session_variable_value(SVariable svar, bool deep_free) { + if (deep_free) + { + PrevValue *prev_value = svar->prev_value; + PrevValue *next_value; + + while (prev_value) + { + if (!svar->typbyval) + pfree(DatumGetPointer(prev_value->value)); + + next_value = prev_value->prev_value; + pfree(prev_value); + + prev_value = next_value; + } + } + /* Clean current value */ if (!svar->isnull) { @@ -403,7 +457,7 @@ remove_invalid_session_variables(bool atEOX) { Oid varid = svar->varid; - free_session_variable_value(svar); + free_session_variable_value(svar, true); hash_search(sessionvars, &varid, HASH_REMOVE, NULL); svar = NULL; } @@ -439,6 +493,94 @@ remove_session_variables_with_reset_at_eox(void) has_session_variables_with_reset_at_eox = false; } +/* + * remove prev values at eox + */ +static void +remove_prev_values_at_eox(bool isCommit) +{ + HASH_SEQ_STATUS status; + SVariable svar; + + if (!sessionvars) + return; + + /* leave quckly, when there are not that variables */ + if (!has_modified_transactional_variables) + return; + + hash_seq_init(&status, sessionvars); + while ((svar = (SVariable) hash_seq_search(&status)) != NULL) + { + if (svar->is_transact && svar->modify_subid != InvalidSubTransactionId) + { + if (isCommit) + { + if (purge_session_variable(svar)) + { + PrevValue *prev_value = svar->prev_value; + + while (prev_value) + { + PrevValue *current_pv = prev_value; + + if (!svar->typbyval && !current_pv->isnull) + pfree(DatumGetPointer(current_pv->value)); + + prev_value = current_pv->prev_value; + pfree(current_pv); + } + } + else + { + hash_search(sessionvars, &svar->varid, HASH_REMOVE, NULL); + svar = NULL; + } + } + else + { + PrevValue *prev_value = svar->prev_value; + + while (prev_value) + { + PrevValue *current_pv = prev_value; + + if (current_pv->modify_subid == InvalidSubTransactionId) + break; + + if (!svar->typbyval && !current_pv->isnull) + pfree(DatumGetPointer(current_pv->value)); + + prev_value = current_pv->prev_value; + pfree(current_pv); + } + + if (prev_value) + { + svar->value = prev_value->value; + svar->isnull = prev_value->isnull; + + pfree(prev_value); + } + else + { + hash_search(sessionvars, &svar->varid, HASH_REMOVE, NULL); + svar = NULL; + } + } + + /* When svar is still valid (not removed from sessionvars */ + if (svar) + { + svar->modify_subid = InvalidSubTransactionId; + svar->prev_value = NULL; + } + } + } + + has_modified_transactional_variables = false; +} + /* * Perform ON COMMIT DROP for temporary session variables, * and remove all dropped variables from memory. @@ -486,6 +628,8 @@ AtPreEOXact_SessionVariables(bool isCommit) remove_invalid_session_variables(true); } + remove_prev_values_at_eox(isCommit); + /* * We have to clean xact_drop_items. All related variables are dropped * now, or lost inside aborted transaction. @@ -631,6 +775,7 @@ setup_session_variable(SVariable svar, Oid varid, bool is_write) svar->is_not_null = varform->varisnotnull; svar->is_immutable = varform->varisimmutable; + svar->is_transact = varform->varistransact; svar->is_domain = (get_typtype(varform->vartype) == TYPTYPE_DOMAIN); svar->domain_check_extra = NULL; @@ -656,6 +801,17 @@ setup_session_variable(SVariable svar, Oid varid, bool is_write) svar->isnull = true; svar->value = (Datum) 0; + if (svar->is_transact) + { + svar->modify_subid = GetCurrentSubTransactionId(); + has_modified_transactional_variables = true; + } + else + svar->modify_subid = InvalidSubTransactionId; + + svar->purge_subid = InvalidSubTransactionId; + svar->prev_value = NULL; + svar->is_valid = true; svar->hashvalue = GetSysCacheHashValue1(VARIABLEOID, @@ -689,6 +845,69 @@ setup_session_variable(SVariable svar, Oid varid, bool is_write) ReleaseSysCache(tup); } +/* + * Try to remove all previous versions related to reverted transactions. + * Returns true, when valid version was found. + */ +static bool +purge_session_variable(SVariable svar) +{ + SubTransactionId current_subid; + PrevValue *prev_value; + bool found = true; + + Assert(svar->is_transact); + + if (svar->modify_subid == InvalidSubTransactionId) + return true; + + current_subid = GetCurrentSubTransactionId(); + + if (svar->modify_subid == current_subid) + return true; + + if (svar->purge_subid == current_subid) + return true; + + if (SubTransactionIsActive(svar->modify_subid)) + { + svar->purge_subid = current_subid; + return true; + } + + prev_value = svar->prev_value; + + while (prev_value) + { + PrevValue *current_pv = prev_value; + + if (current_pv->modify_subid == InvalidSubTransactionId || + SubTransactionIsActive(current_pv->modify_subid)) + { + svar->value = current_pv->value; + svar->isnull = current_pv->isnull; + svar->modify_subid = current_pv->modify_subid; + + prev_value = current_pv->prev_value; + pfree(current_pv); + + found = true; + break; + } + + if (!svar->typbyval && !current_pv->isnull) + pfree(DatumGetPointer(current_pv->value)); + + prev_value = current_pv->prev_value; + pfree(current_pv); + } + + svar->prev_value = prev_value; + svar->purge_subid = current_subid; + + return found; +} + /* * Assign some content to the session variable. It's copied to * SVariableMemoryContext if necessary. @@ -701,6 +920,10 @@ set_session_variable(SVariable svar, Datum value, bool isnull) Datum newval; SVariableData locsvar, *_svar; + SubTransactionId current_subid = GetCurrentSubTransactionId(); + SubTransactionId prev_purge_subid = InvalidSubTransactionId; + bool save_prev_value; + PrevValue *prev_value; Assert(svar); Assert(!isnull || value == (Datum) 0); @@ -736,6 +959,21 @@ set_session_variable(SVariable svar, Datum value, bool isnull) else _svar = svar; + if (_svar->is_transact && _svar->create_lsn == svar->create_lsn) + { + Assert(svar->typid == _svar->typid); + Assert(svar->typbyval == _svar->typbyval); + Assert(svar->typlen == _svar->typlen); + + save_prev_value = svar->modify_subid != current_subid; + prev_value = svar->prev_value; + } + else + { + save_prev_value = false; + prev_value = NULL; + } + if (!isnull) { MemoryContext oldcxt = MemoryContextSwitchTo(SVariableMemoryContext); @@ -747,7 +985,37 @@ set_session_variable(SVariable svar, Datum value, bool isnull) else newval = value; - free_session_variable_value(svar); + if (save_prev_value) + { + volatile PrevValue *new_prev_value; + + PG_TRY(); + { + new_prev_value = MemoryContextAlloc(SVariableMemoryContext, + sizeof(PrevValue)); + } + PG_CATCH(); + { + /* release mem from persistent content */ + if (newval != value) + pfree(DatumGetPointer(newval)); + PG_RE_THROW(); + } + PG_END_TRY(); + + new_prev_value->value = svar->value; + new_prev_value->isnull = svar->isnull; + new_prev_value->modify_subid = svar->modify_subid; + new_prev_value->prev_value = prev_value; + + prev_value = (PrevValue *) new_prev_value; + prev_purge_subid = svar->purge_subid; + + has_modified_transactional_variables = true; + + } + else + free_session_variable_value(svar, prev_value == NULL); /* We can overwrite old variable now. No error expected */ if (svar != _svar) @@ -755,6 +1023,9 @@ set_session_variable(SVariable svar, Datum value, bool isnull) svar->value = newval; svar->isnull = isnull; + svar->modify_subid = current_subid; + svar->purge_subid = prev_purge_subid; + svar->prev_value = prev_value; /* don't allow more changes of value when variable is IMMUTABLE */ if (svar->is_immutable) @@ -870,6 +1141,8 @@ get_session_variable(Oid varid) else svar->is_valid = false; +reinit: + /* * Force setup for not yet initialized variables or variables that cannot * be validated. @@ -902,6 +1175,28 @@ get_session_variable(Oid varid) varid); } + /* + * Transactional variables should be purged before (remove + * versions created by possibly reverted subtransactions). + */ + if (svar->is_transact && + svar->modify_subid != GetCurrentSubTransactionId() && + svar->modify_subid != InvalidSubTransactionId) + { + if (!purge_session_variable(svar)) + { + /* force reinit */ + svar->is_valid = false; + + /* + * In next iteration modify_subid should be + * InvalidSubTransactionId or current subid, + * so there is not risk of infinity cycle. + */ + goto reinit; + } + } + /* Ensure so returned data is still correct domain */ if (svar->is_domain) { diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index 4b9726041d..c746601702 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -683,7 +683,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); json_object_constructor_null_clause_opt json_array_constructor_null_clause_opt -%type OptNotNull OptImmutable +%type OptNotNull OptImmutable OptTransactional /* * Non-keyword token types. These are hard-wired into the "flex" lexer. @@ -788,7 +788,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); SUBSCRIPTION SUBSTRING SUPPORT SYMMETRIC SYSID SYSTEM_P SYSTEM_USER TABLE TABLES TABLESAMPLE TABLESPACE TARGET TEMP TEMPLATE TEMPORARY TEXT_P THEN - TIES TIME TIMESTAMP TO TRAILING TRANSACTION TRANSFORM + TIES TIME TIMESTAMP TO TRAILING TRANSACTION TRANSACTIONAL TRANSFORM TREAT TRIGGER TRIM TRUE_P TRUNCATE TRUSTED TYPE_P TYPES_P @@ -5232,31 +5232,33 @@ create_extension_opt_item: *****************************************************************************/ CreateSessionVarStmt: - CREATE OptTemp OptImmutable VARIABLE qualified_name opt_as Typename opt_collate_clause OptNotNull OptSessionVarDefExpr OnEOXActionOption + CREATE OptTemp OptTransactional OptImmutable VARIABLE qualified_name opt_as Typename opt_collate_clause OptNotNull OptSessionVarDefExpr OnEOXActionOption { CreateSessionVarStmt *n = makeNode(CreateSessionVarStmt); - $5->relpersistence = $2; - n->is_immutable = $3; - n->variable = $5; - n->typeName = $7; - n->collClause = (CollateClause *) $8; - n->is_not_null = $9; - n->defexpr = $10; - n->eoxaction = $11; + $6->relpersistence = $2; + n->is_immutable = $4; + n->is_transact = $3; + n->variable = $6; + n->typeName = $8; + n->collClause = (CollateClause *) $9; + n->is_not_null = $10; + n->defexpr = $11; + n->eoxaction = $12; n->if_not_exists = false; $$ = (Node *) n; } - | CREATE OptTemp OptImmutable VARIABLE IF_P NOT EXISTS qualified_name opt_as Typename opt_collate_clause OptNotNull OptSessionVarDefExpr OnEOXActionOption + | CREATE OptTemp OptTransactional OptImmutable VARIABLE IF_P NOT EXISTS qualified_name opt_as Typename opt_collate_clause OptNotNull OptSessionVarDefExpr OnEOXActionOption { CreateSessionVarStmt *n = makeNode(CreateSessionVarStmt); - $8->relpersistence = $2; - n->is_immutable = $3; - n->variable = $8; - n->typeName = $10; - n->collClause = (CollateClause *) $11; - n->is_not_null = $12; - n->defexpr = $13; - n->eoxaction = $14; + $9->relpersistence = $2; + n->is_immutable = $4; + n->is_transact = $3; + n->variable = $9; + n->typeName = $11; + n->collClause = (CollateClause *) $12; + n->is_not_null = $13; + n->defexpr = $14; + n->eoxaction = $15; n->if_not_exists = true; $$ = (Node *) n; } @@ -5284,6 +5286,12 @@ OptImmutable: IMMUTABLE { $$ = true; } | /* EMPTY */ { $$ = false; } ; +OptTransactional: + TRANSACTION { $$ = true; } + | TRANSACTIONAL { $$ = true; } + | /* EMPTY */ { $$ = false; } + ; + /***************************************************************************** * * ALTER EXTENSION name UPDATE [ TO version ] @@ -18045,6 +18053,7 @@ unreserved_keyword: | TEXT_P | TIES | TRANSACTION + | TRANSACTIONAL | TRANSFORM | TRIGGER | TRUNCATE @@ -18695,6 +18704,7 @@ bare_label_keyword: | TIMESTAMP | TRAILING | TRANSACTION + | TRANSACTIONAL | TRANSFORM | TREAT | TRIGGER diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c index 4d2ac92ef7..5060c4f5fb 100644 --- a/src/bin/pg_dump/pg_dump.c +++ b/src/bin/pg_dump/pg_dump.c @@ -5315,6 +5315,7 @@ getVariables(Archive *fout) int i_varcollation; int i_varisnotnull; int i_varisimmutable; + int i_varistransact; int i_varacl; int i_acldefault; int i, @@ -5338,6 +5339,7 @@ getVariables(Archive *fout) "THEN v.varcollation ELSE 0 END AS varcollation,\n" "v.varisnotnull,\n" "v.varisimmutable,\n" + "v.varistransact,\n" "pg_catalog.pg_get_expr(v.vardefexpr,0) as vardefexpr,\n" "v.varowner,\n" "v.varacl,\n" @@ -5361,6 +5363,7 @@ getVariables(Archive *fout) i_varcollation = PQfnumber(res, "varcollation"); i_varisnotnull = PQfnumber(res, "varisnotnull"); i_varisimmutable = PQfnumber(res, "varisimmutable"); + i_varistransact = PQfnumber(res, "varistransact"); i_varowner = PQfnumber(res, "varowner"); i_varacl = PQfnumber(res, "varacl"); @@ -5387,6 +5390,7 @@ getVariables(Archive *fout) varinfo[i].varcollation = atooid(PQgetvalue(res, i, i_varcollation)); varinfo[i].varisnotnull = *(PQgetvalue(res, i, i_varisnotnull)) == 't'; varinfo[i].varisimmutable = *(PQgetvalue(res, i, i_varisimmutable)) == 't'; + varinfo[i].varistransact = *(PQgetvalue(res, i, i_varistransact)) == 't'; varinfo[i].dacl.acl = pg_strdup(PQgetvalue(res, i, i_varacl)); varinfo[i].dacl.acldefault = pg_strdup(PQgetvalue(res, i, i_acldefault)); @@ -5437,6 +5441,7 @@ dumpVariable(Archive *fout, const VariableInfo *varinfo) const char *vardefexpr; const char *vareoxaction; const char *varisimmutable; + const char *varistransact; Oid varcollation; bool varisnotnull; @@ -5454,12 +5459,13 @@ dumpVariable(Archive *fout, const VariableInfo *varinfo) varcollation = varinfo->varcollation; varisnotnull = varinfo->varisnotnull; varisimmutable = varinfo->varisimmutable ? "IMMUTABLE " : ""; + varistransact = varinfo->varistransact ? "TRANSACTIONAL " : ""; appendPQExpBuffer(delq, "DROP VARIABLE %s;\n", qualvarname); - appendPQExpBuffer(query, "CREATE %sVARIABLE %s AS %s", - varisimmutable, qualvarname, vartypname); + appendPQExpBuffer(query, "CREATE %s%sVARIABLE %s AS %s", + varistransact, varisimmutable, qualvarname, vartypname); if (OidIsValid(varcollation)) { diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h index 159dc4c02f..bf7d4e38c9 100644 --- a/src/bin/pg_dump/pg_dump.h +++ b/src/bin/pg_dump/pg_dump.h @@ -712,6 +712,7 @@ typedef struct _VariableInfo const char *rolname; /* name of owner, or empty string */ bool varisnotnull; bool varisimmutable; + bool varistransact; } VariableInfo; /* diff --git a/src/bin/pg_dump/t/002_pg_dump.pl b/src/bin/pg_dump/t/002_pg_dump.pl index ae310961ab..9c6c6a583c 100644 --- a/src/bin/pg_dump/t/002_pg_dump.pl +++ b/src/bin/pg_dump/t/002_pg_dump.pl @@ -4049,6 +4049,42 @@ my %tests = ( }, }, + 'CREATE TRANSACTIONAL VARIABLE test_variable' => { + all_runs => 1, + catch_all => 'CREATE ... commands', + create_order => 61, + create_sql => 'CREATE TRANSACTIONAL VARIABLE dump_test.variable8 AS integer', + regexp => qr/^ + \QCREATE TRANSACTIONAL VARIABLE dump_test.variable8 AS integer;\E/xm, + like => { + %full_runs, + %dump_test_schema_runs, + section_pre_data => 1, + }, + unlike => { + exclude_dump_test_schema => 1, + only_dump_measurement => 1, + }, + }, + + 'CREATE TRANSACTIONAL IMMUTABLE VARIABLE test_variable' => { + all_runs => 1, + catch_all => 'CREATE ... commands', + create_order => 61, + create_sql => 'CREATE TRANSACTIONAL IMMUTABLE VARIABLE dump_test.variable9 AS integer', + regexp => qr/^ + \QCREATE TRANSACTIONAL IMMUTABLE VARIABLE dump_test.variable9 AS integer;\E/xm, + like => { + %full_runs, + %dump_test_schema_runs, + section_pre_data => 1, + }, + unlike => { + exclude_dump_test_schema => 1, + only_dump_measurement => 1, + }, + }, + 'CREATE VIEW test_view' => { create_order => 61, create_sql => 'CREATE VIEW dump_test.test_view diff --git a/src/bin/psql/describe.c b/src/bin/psql/describe.c index e25e12dd46..23ef475532 100644 --- a/src/bin/psql/describe.c +++ b/src/bin/psql/describe.c @@ -5149,7 +5149,7 @@ listVariables(const char *pattern, bool verbose) PQExpBufferData buf; PGresult *res; printQueryOpt myopt = pset.popt; - static const bool translate_columns[] = {false, false, false, false, false, false, false, false, false, false, false}; + static const bool translate_columns[] = {false, false, false, false, false, false, false, false, false, false, false, false}; initPQExpBuffer(&buf); @@ -5162,6 +5162,7 @@ listVariables(const char *pattern, bool verbose) " pg_catalog.pg_get_userbyid(v.varowner) as \"%s\",\n" " NOT v.varisnotnull as \"%s\",\n" " NOT v.varisimmutable as \"%s\",\n" + " v.varistransact as \"%s\",\n" " pg_catalog.pg_get_expr(v.vardefexpr, 0) as \"%s\",\n" " CASE v.vareoxaction\n" " WHEN 'd' THEN 'ON COMMIT DROP'\n" @@ -5174,6 +5175,7 @@ listVariables(const char *pattern, bool verbose) gettext_noop("Owner"), gettext_noop("Nullable"), gettext_noop("Mutable"), + gettext_noop("Transactional"), gettext_noop("Default"), gettext_noop("Transactional end action")); diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c index e503b22707..e071d62667 100644 --- a/src/bin/psql/tab-complete.c +++ b/src/bin/psql/tab-complete.c @@ -1284,6 +1284,8 @@ static const pgsql_thing_t words_after_create[] = { * TABLE ... */ {"TEXT SEARCH", NULL, NULL, NULL}, {"TRANSFORM", NULL, NULL, NULL, NULL, THING_NO_ALTER}, + {"TRANSACTIONAL", NULL, NULL, NULL, NULL, THING_NO_DROP | THING_NO_ALTER}, /* for CREATE TRANSACTIONAL + * VARIABLE ... */ {"TRIGGER", "SELECT tgname FROM pg_catalog.pg_trigger WHERE tgname LIKE '%s' AND NOT tgisinternal"}, {"TYPE", NULL, NULL, &Query_for_list_of_datatypes}, {"UNIQUE", NULL, NULL, NULL, NULL, THING_NO_DROP | THING_NO_ALTER}, /* for CREATE UNIQUE @@ -3601,8 +3603,11 @@ psql_completion(const char *text, int start, int end) } /* CREATE VARIABLE --- is allowed inside CREATE SCHEMA, so use TailMatches */ /* Complete CREATE VARIABLE with AS */ + else if (Matches("CREATE", "TRANSACTION|TRANSACTIONAL")) + COMPLETE_WITH("IMMUTABLE", "VARIABLE"); else if (TailMatches("CREATE", "VARIABLE", MatchAny) || TailMatches("TEMP|TEMPORARY", "VARIABLE", MatchAny) || + TailMatches("TRANSACTION|TRANSACTIONAL", "VARIABLE", MatchAny) || TailMatches("IMMUTABLE", "VARIABLE", MatchAny)) COMPLETE_WITH("AS"); else if (TailMatches("VARIABLE", MatchAny, "AS")) diff --git a/src/include/catalog/pg_variable.h b/src/include/catalog/pg_variable.h index 43c8bc9658..e7e6a5dce0 100644 --- a/src/include/catalog/pg_variable.h +++ b/src/include/catalog/pg_variable.h @@ -60,6 +60,9 @@ CATALOG(pg_variable,9222,VariableRelationId) /* don't allow changes */ bool varisimmutable BKI_DEFAULT(f); + /* supports transactions */ + bool varistransact BKI_DEFAULT(f); + /* action on transaction end */ char vareoxaction BKI_DEFAULT(n); diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index d92b9f7801..f0fb412254 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -3459,6 +3459,7 @@ typedef struct CreateSessionVarStmt bool if_not_exists; /* do nothing if it already exists */ bool is_not_null; /* disallow nulls */ bool is_immutable; /* don't allow changes */ + bool is_transact; /* supports transactions */ Node *defexpr; /* default expression */ char eoxaction; /* on commit action */ } CreateSessionVarStmt; diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h index 2e88d7d950..753cf360db 100644 --- a/src/include/parser/kwlist.h +++ b/src/include/parser/kwlist.h @@ -457,6 +457,7 @@ PG_KEYWORD("timestamp", TIMESTAMP, COL_NAME_KEYWORD, BARE_LABEL) PG_KEYWORD("to", TO, RESERVED_KEYWORD, AS_LABEL) PG_KEYWORD("trailing", TRAILING, RESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("transaction", TRANSACTION, UNRESERVED_KEYWORD, BARE_LABEL) +PG_KEYWORD("transactional", TRANSACTIONAL, UNRESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("transform", TRANSFORM, UNRESERVED_KEYWORD, BARE_LABEL) PG_KEYWORD("treat", TREAT, COL_NAME_KEYWORD, BARE_LABEL) PG_KEYWORD("trigger", TRIGGER, UNRESERVED_KEYWORD, BARE_LABEL) diff --git a/src/test/regress/expected/psql.out b/src/test/regress/expected/psql.out index 451fdde31c..75f173d233 100644 --- a/src/test/regress/expected/psql.out +++ b/src/test/regress/expected/psql.out @@ -5833,20 +5833,20 @@ CREATE ROLE regress_variable_owner; SET ROLE TO regress_variable_owner; CREATE VARIABLE var1 AS varchar COLLATE "C"; \dV+ var1 - List of variables - Schema | Name | Type | Collation | Owner | Nullable | Mutable | Default | Transactional end action | Access privileges | Description ---------+------+-------------------+-----------+------------------------+----------+---------+---------+--------------------------+-------------------+------------- - public | var1 | character varying | C | regress_variable_owner | t | t | | | | + List of variables + Schema | Name | Type | Collation | Owner | Nullable | Mutable | Transactional | Default | Transactional end action | Access privileges | Description +--------+------+-------------------+-----------+------------------------+----------+---------+---------------+---------+--------------------------+-------------------+------------- + public | var1 | character varying | C | regress_variable_owner | t | t | f | | | | (1 row) GRANT SELECT ON VARIABLE var1 TO PUBLIC; COMMENT ON VARIABLE var1 IS 'some description'; \dV+ var1 - List of variables - Schema | Name | Type | Collation | Owner | Nullable | Mutable | Default | Transactional end action | Access privileges | Description ---------+------+-------------------+-----------+------------------------+----------+---------+---------+--------------------------+--------------------------------------------------+------------------ - public | var1 | character varying | C | regress_variable_owner | t | t | | | regress_variable_owner=rw/regress_variable_owner+| some description - | | | | | | | | | =r/regress_variable_owner | + List of variables + Schema | Name | Type | Collation | Owner | Nullable | Mutable | Transactional | Default | Transactional end action | Access privileges | Description +--------+------+-------------------+-----------+------------------------+----------+---------+---------------+---------+--------------------------+--------------------------------------------------+------------------ + public | var1 | character varying | C | regress_variable_owner | t | t | f | | | regress_variable_owner=rw/regress_variable_owner+| some description + | | | | | | | | | | =r/regress_variable_owner | (1 row) DROP VARIABLE var1; @@ -6314,9 +6314,9 @@ List of schemas (0 rows) \dV "no.such.variable" - List of variables - Schema | Name | Type | Collation | Owner | Nullable | Mutable | Default | Transactional end action ---------+------+------+-----------+-------+----------+---------+---------+-------------------------- + List of variables + Schema | Name | Type | Collation | Owner | Nullable | Mutable | Transactional | Default | Transactional end action +--------+------+------+-----------+-------+----------+---------+---------------+---------+-------------------------- (0 rows) -- again, but with dotted schema qualifications. @@ -6489,9 +6489,9 @@ improper qualified name (too many dotted names): "no.such.schema"."no.such.insta \dy "no.such.schema"."no.such.event.trigger" improper qualified name (too many dotted names): "no.such.schema"."no.such.event.trigger" \dV "no.such.schema"."no.such.variable" - List of variables - Schema | Name | Type | Collation | Owner | Nullable | Mutable | Default | Transactional end action ---------+------+------+-----------+-------+----------+---------+---------+-------------------------- + List of variables + Schema | Name | Type | Collation | Owner | Nullable | Mutable | Transactional | Default | Transactional end action +--------+------+------+-----------+-------+----------+---------+---------------+---------+-------------------------- (0 rows) -- again, but with current database and dotted schema qualifications. @@ -6628,9 +6628,9 @@ List of text search templates (0 rows) \dV regression."no.such.schema"."no.such.variable" - List of variables - Schema | Name | Type | Collation | Owner | Nullable | Mutable | Default | Transactional end action ---------+------+------+-----------+-------+----------+---------+---------+-------------------------- + List of variables + Schema | Name | Type | Collation | Owner | Nullable | Mutable | Transactional | Default | Transactional end action +--------+------+------+-----------+-------+----------+---------+---------------+---------+-------------------------- (0 rows) -- again, but with dotted database and dotted schema qualifications. diff --git a/src/test/regress/expected/session_variables.out b/src/test/regress/expected/session_variables.out index 103b0ca6cd..b9e12fea05 100644 --- a/src/test/regress/expected/session_variables.out +++ b/src/test/regress/expected/session_variables.out @@ -45,11 +45,11 @@ SET ROLE TO regress_variable_owner; CREATE VARIABLE svartest.var1 AS int; SET ROLE TO DEFAULT; \dV+ svartest.var1 - List of variables - Schema | Name | Type | Collation | Owner | Nullable | Mutable | Default | Transactional end action | Access privileges | Description -----------+------+---------+-----------+------------------------+----------+---------+---------+--------------------------+--------------------------------------------------+------------- - svartest | var1 | integer | | regress_variable_owner | t | t | | | regress_variable_owner=rw/regress_variable_owner+| - | | | | | | | | | regress_variable_reader=r/regress_variable_owner | + List of variables + Schema | Name | Type | Collation | Owner | Nullable | Mutable | Transactional | Default | Transactional end action | Access privileges | Description +----------+------+---------+-----------+------------------------+----------+---------+---------------+---------+--------------------------+--------------------------------------------------+------------- + svartest | var1 | integer | | regress_variable_owner | t | t | f | | | regress_variable_owner=rw/regress_variable_owner+| + | | | | | | | | | | regress_variable_reader=r/regress_variable_owner | (1 row) DROP VARIABLE svartest.var1; @@ -1731,3 +1731,103 @@ SELECT var1; LET var1 = 30; ERROR: session variable "public.var1" is declared IMMUTABLE DROP VARIABLE var1; +-- test transactional variables +CREATE TRANSACTION VARIABLE tv AS int DEFAULT 0; +BEGIN; + LET tv = 100; + SELECT tv; + tv +----- + 100 +(1 row) + +ROLLBACK; +SELECT tv; + tv +---- + 0 +(1 row) + +LET tv = 100; +BEGIN; + LET tv = 1000; +COMMIT; +SELECT tv; + tv +------ + 1000 +(1 row) + +BEGIN; + LET tv = 0; + SELECT tv; + tv +---- + 0 +(1 row) + +ROLLBACK; +SELECT tv; + tv +------ + 1000 +(1 row) + +-- test subtransactions +BEGIN; + LET tv = 1; +SAVEPOINT x1; + LET tv = 2; +SAVEPOINT x2; + LET tv = 3; +ROLLBACK TO x2; + SELECT tv; + tv +---- + 2 +(1 row) + + LET tv = 10; +ROLLBACK TO x1; + SELECT tv; + tv +---- + 1 +(1 row) + +ROLLBACK; +SELECT tv; + tv +------ + 1000 +(1 row) + +BEGIN; + LET tv = 1; +SAVEPOINT x1; + LET tv = 2; +SAVEPOINT x2; + LET tv = 3; +ROLLBACK TO x2; + SELECT tv; + tv +---- + 2 +(1 row) + + LET tv = 10; +ROLLBACK TO x1; + SELECT tv; + tv +---- + 1 +(1 row) + +COMMIT; +SELECT tv; + tv +---- + 1 +(1 row) + +DROP VARIABLE tv; diff --git a/src/test/regress/sql/session_variables.sql b/src/test/regress/sql/session_variables.sql index 400a0e00d6..3cd4c03801 100644 --- a/src/test/regress/sql/session_variables.sql +++ b/src/test/regress/sql/session_variables.sql @@ -1182,3 +1182,61 @@ SELECT var1; LET var1 = 30; DROP VARIABLE var1; + +-- test transactional variables +CREATE TRANSACTION VARIABLE tv AS int DEFAULT 0; + +BEGIN; + LET tv = 100; + SELECT tv; +ROLLBACK; + +SELECT tv; + +LET tv = 100; +BEGIN; + LET tv = 1000; +COMMIT; + +SELECT tv; + +BEGIN; + LET tv = 0; + SELECT tv; +ROLLBACK; + +SELECT tv; + +-- test subtransactions + +BEGIN; + LET tv = 1; +SAVEPOINT x1; + LET tv = 2; +SAVEPOINT x2; + LET tv = 3; +ROLLBACK TO x2; + SELECT tv; + LET tv = 10; +ROLLBACK TO x1; + SELECT tv; +ROLLBACK; + +SELECT tv; + +BEGIN; + LET tv = 1; +SAVEPOINT x1; + LET tv = 2; +SAVEPOINT x2; + LET tv = 3; +ROLLBACK TO x2; + SELECT tv; + LET tv = 10; +ROLLBACK TO x1; + SELECT tv; +COMMIT; + +SELECT tv; + +DROP VARIABLE tv; -- 2.45.1