From b565c793914275c6daf4b169a7d7cde3a2a028aa Mon Sep 17 00:00:00 2001 From: Amul Sul Date: Wed, 15 Nov 2023 18:04:51 +0530 Subject: [PATCH v4 1/2] Allow to change generated column expression --- doc/src/sgml/ref/alter_table.sgml | 13 ++ src/backend/commands/tablecmds.c | 111 +++++++++++- src/backend/parser/gram.y | 10 ++ src/bin/psql/tab-complete.c | 10 +- src/include/nodes/parsenodes.h | 1 + .../test_ddl_deparse/test_ddl_deparse.c | 3 + src/test/regress/expected/generated.out | 167 +++++++++++++++--- src/test/regress/sql/generated.sql | 36 +++- 8 files changed, 321 insertions(+), 30 deletions(-) diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index 2c4138e4e9f..c5c0ac6e276 100644 --- a/doc/src/sgml/ref/alter_table.sgml +++ b/doc/src/sgml/ref/alter_table.sgml @@ -46,6 +46,7 @@ ALTER TABLE [ IF EXISTS ] name ALTER [ COLUMN ] column_name SET DEFAULT expression ALTER [ COLUMN ] column_name DROP DEFAULT ALTER [ COLUMN ] column_name { SET | DROP } NOT NULL + ALTER [ COLUMN ] column_name SET EXPRESSION AS ( expression ) ALTER [ COLUMN ] column_name DROP EXPRESSION [ IF EXISTS ] ALTER [ COLUMN ] column_name ADD GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY [ ( sequence_options ) ] ALTER [ COLUMN ] column_name { SET GENERATED { ALWAYS | BY DEFAULT } | SET sequence_option | RESTART [ [ WITH ] restart ] } [...] @@ -256,6 +257,18 @@ WITH ( MODULUS numeric_literal, REM + + SET EXPRESSION AS + + + This form replaces the expression of a generated column. Existing + data in the column is rewritten and all the future changes will + apply the new + generation expression. + + + + DROP EXPRESSION [ IF EXISTS ] diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 323d9bf8702..63debf1c376 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -455,6 +455,9 @@ static ObjectAddress ATExecAddIdentity(Relation rel, const char *colName, static ObjectAddress ATExecSetIdentity(Relation rel, const char *colName, Node *def, LOCKMODE lockmode); static ObjectAddress ATExecDropIdentity(Relation rel, const char *colName, bool missing_ok, LOCKMODE lockmode); +static ObjectAddress ATExecSetExpression(AlteredTableInfo *tab, Relation rel, + const char *colName, Node *newDefault, + LOCKMODE lockmode); static void ATPrepDropExpression(Relation rel, AlterTableCmd *cmd, bool recurse, bool recursing, LOCKMODE lockmode); static ObjectAddress ATExecDropExpression(Relation rel, const char *colName, bool missing_ok, LOCKMODE lockmode); static ObjectAddress ATExecSetStatistics(Relation rel, const char *colName, int16 colNum, @@ -4548,6 +4551,7 @@ AlterTableGetLockLevel(List *cmds) case AT_AddIdentity: case AT_DropIdentity: case AT_SetIdentity: + case AT_SetExpression: case AT_DropExpression: case AT_SetCompression: cmd_lockmode = AccessExclusiveLock; @@ -4849,6 +4853,11 @@ ATPrepCmd(List **wqueue, Relation rel, AlterTableCmd *cmd, ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode, context); pass = AT_PASS_COL_ATTRS; break; + case AT_SetExpression: /* ALTER COLUMN SET EXPRESSION AS */ + ATSimplePermissions(cmd->subtype, rel, ATT_TABLE | ATT_FOREIGN_TABLE); + ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode, context); + pass = AT_PASS_MISC; + break; case AT_DropExpression: /* ALTER COLUMN DROP EXPRESSION */ ATSimplePermissions(cmd->subtype, rel, ATT_TABLE | ATT_FOREIGN_TABLE); ATSimpleRecursion(wqueue, rel, cmd, recurse, lockmode, context); @@ -5234,6 +5243,9 @@ ATExecCmd(List **wqueue, AlteredTableInfo *tab, case AT_SetAttNotNull: /* set pg_attribute.attnotnull */ address = ATExecSetAttNotNull(wqueue, rel, cmd->name, lockmode); break; + case AT_SetExpression: + address = ATExecSetExpression(tab, rel, cmd->name, cmd->def, lockmode); + break; case AT_DropExpression: address = ATExecDropExpression(rel, cmd->name, cmd->missing_ok, lockmode); break; @@ -6361,6 +6373,8 @@ alter_table_type_to_string(AlterTableType cmdtype) return "ALTER COLUMN ... SET NOT NULL"; case AT_SetAttNotNull: return NULL; /* not real grammar */ + case AT_SetExpression: + return "ALTER COLUMN ... SET EXPRESSION AS"; case AT_DropExpression: return "ALTER COLUMN ... DROP EXPRESSION"; case AT_SetStatistics: @@ -8011,8 +8025,10 @@ ATExecColumnDefault(Relation rel, const char *colName, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("column \"%s\" of relation \"%s\" is a generated column", colName, RelationGetRelationName(rel)), - newDefault || TupleDescAttr(tupdesc, attnum - 1)->attgenerated != ATTRIBUTE_GENERATED_STORED ? 0 : + TupleDescAttr(tupdesc, attnum - 1)->attgenerated != ATTRIBUTE_GENERATED_STORED ? 0 : /* translator: %s is an SQL ALTER command */ + newDefault ? errhint("Use %s instead.", + "ALTER TABLE ... ALTER COLUMN ... SET EXPRESSION") : errhint("Use %s instead.", "ALTER TABLE ... ALTER COLUMN ... DROP EXPRESSION"))); @@ -8311,6 +8327,99 @@ ATExecDropIdentity(Relation rel, const char *colName, bool missing_ok, LOCKMODE return address; } +/* + * ALTER TABLE ALTER COLUMN SET EXPRESSION AS + * + * Return the address of the affected column. + */ +static ObjectAddress +ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName, + Node *newDefault, LOCKMODE lockmode) +{ + HeapTuple tuple; + Form_pg_attribute attTup; + AttrNumber attnum; + Oid attrdefoid; + ObjectAddress address; + Expr *defval; + NewColumnValue *newval; + RawColumnDefault *rawEnt; + + tuple = SearchSysCacheAttName(RelationGetRelid(rel), colName); + if (!HeapTupleIsValid(tuple)) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_COLUMN), + errmsg("column \"%s\" of relation \"%s\" does not exist", + colName, RelationGetRelationName(rel)))); + + attTup = (Form_pg_attribute) GETSTRUCT(tuple); + attnum = attTup->attnum; + + if (attnum <= 0) + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("cannot alter system column \"%s\"", + colName))); + + if (attTup->attgenerated != ATTRIBUTE_GENERATED_STORED) + ereport(ERROR, + (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE), + errmsg("column \"%s\" of relation \"%s\" is not a stored generated column", + colName, RelationGetRelationName(rel)))); + ReleaseSysCache(tuple); + + /* + * Drop the dependency records of the GENERATED expression, in particular + * its INTERNAL dependency on the column, which would otherwise cause + * dependency.c to refuse to perform the deletion. + */ + attrdefoid = GetAttrDefaultOid(RelationGetRelid(rel), attnum); + if (!OidIsValid(attrdefoid)) + elog(ERROR, "could not find attrdef tuple for relation %u attnum %d", + RelationGetRelid(rel), attnum); + (void) deleteDependencyRecordsFor(AttrDefaultRelationId, attrdefoid, false); + + /* Make above changes visible */ + CommandCounterIncrement(); + + /* + * Get rid of the GENERATED expression itself. We use RESTRICT here for + * safety, but at present we do not expect anything to depend on the + * default. + */ + RemoveAttrDefault(RelationGetRelid(rel), attnum, DROP_RESTRICT, + false, false); + + /* Prepare to store the new expression, in the catalogs */ + rawEnt = (RawColumnDefault *) palloc(sizeof(RawColumnDefault)); + rawEnt->attnum = attnum; + rawEnt->raw_default = newDefault; + rawEnt->missingMode = false; + rawEnt->generated = ATTRIBUTE_GENERATED_STORED; + + /* Store the generated expression */ + AddRelationNewConstraints(rel, list_make1(rawEnt), NIL, + false, true, false, NULL); + + /* Make above new expression visible */ + CommandCounterIncrement(); + + /* Prepare for table rewrite */ + defval = (Expr *) build_column_default(rel, attnum); + + newval = (NewColumnValue *) palloc0(sizeof(NewColumnValue)); + newval->attnum = attnum; + newval->expr = expression_planner(defval); + newval->is_generated = true; + + tab->newvals = lappend(tab->newvals, newval); + tab->rewrite |= AT_REWRITE_DEFAULT_VAL; + + ObjectAddressSubSet(address, RelationRelationId, + RelationGetRelid(rel), attnum); + return address; +} + /* * ALTER TABLE ALTER COLUMN DROP EXPRESSION */ diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index c224df4eccc..b3c0e51230f 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -2404,6 +2404,16 @@ alter_table_cmd: n->name = $3; $$ = (Node *) n; } + /* ALTER TABLE ALTER [COLUMN] SET EXPRESSION AS */ + | ALTER opt_column ColId SET EXPRESSION AS '(' a_expr ')' + { + AlterTableCmd *n = makeNode(AlterTableCmd); + + n->subtype = AT_SetExpression; + n->name = $3; + n->def = $8; + $$ = (Node *) n; + } /* ALTER TABLE ALTER [COLUMN] DROP EXPRESSION */ | ALTER opt_column ColId DROP EXPRESSION { diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c index 006e10f5d2d..019d55a659d 100644 --- a/src/bin/psql/tab-complete.c +++ b/src/bin/psql/tab-complete.c @@ -2483,7 +2483,7 @@ psql_completion(const char *text, int start, int end) /* ALTER TABLE ALTER [COLUMN] SET */ else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET") || Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET")) - COMPLETE_WITH("(", "COMPRESSION", "DEFAULT", "GENERATED", "NOT NULL", "STATISTICS", "STORAGE", + COMPLETE_WITH("(", "COMPRESSION", "DEFAULT", "EXPRESSION", "GENERATED", "NOT NULL", "STATISTICS", "STORAGE", /* a subset of ALTER SEQUENCE options */ "INCREMENT", "MINVALUE", "MAXVALUE", "START", "NO", "CACHE", "CYCLE"); /* ALTER TABLE ALTER [COLUMN] SET ( */ @@ -2494,6 +2494,14 @@ psql_completion(const char *text, int start, int end) else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "COMPRESSION") || Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "COMPRESSION")) COMPLETE_WITH("DEFAULT", "PGLZ", "LZ4"); + /* ALTER TABLE ALTER [COLUMN] SET EXPRESSION */ + else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "EXPRESSION") || + Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "EXPRESSION")) + COMPLETE_WITH("AS"); + /* ALTER TABLE ALTER [COLUMN] SET EXPRESSION AS */ + else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "EXPRESSION", "AS") || + Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "EXPRESSION", "AS")) + COMPLETE_WITH("("); /* ALTER TABLE ALTER [COLUMN] SET GENERATED */ else if (Matches("ALTER", "TABLE", MatchAny, "ALTER", "COLUMN", MatchAny, "SET", "GENERATED") || Matches("ALTER", "TABLE", MatchAny, "ALTER", MatchAny, "SET", "GENERATED")) diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index e494309da8d..cd08391dcb0 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -2192,6 +2192,7 @@ typedef enum AlterTableType AT_DropNotNull, /* alter column drop not null */ AT_SetNotNull, /* alter column set not null */ AT_SetAttNotNull, /* set attnotnull w/o a constraint */ + AT_SetExpression, /* alter column set expression */ AT_DropExpression, /* alter column drop expression */ AT_SetStatistics, /* alter column set statistics */ AT_SetOptions, /* alter column set ( options ) */ diff --git a/src/test/modules/test_ddl_deparse/test_ddl_deparse.c b/src/test/modules/test_ddl_deparse/test_ddl_deparse.c index 0302f79bb71..d34c7719dca 100644 --- a/src/test/modules/test_ddl_deparse/test_ddl_deparse.c +++ b/src/test/modules/test_ddl_deparse/test_ddl_deparse.c @@ -132,6 +132,9 @@ get_altertable_subcmdinfo(PG_FUNCTION_ARGS) case AT_SetAttNotNull: strtype = "SET ATTNOTNULL"; break; + case AT_SetExpression: + strtype = "SET EXPRESSION AS"; + break; case AT_DropExpression: strtype = "DROP EXPRESSION"; break; diff --git a/src/test/regress/expected/generated.out b/src/test/regress/expected/generated.out index a2f38d0f50a..1cd7d6c6b35 100644 --- a/src/test/regress/expected/generated.out +++ b/src/test/regress/expected/generated.out @@ -785,30 +785,119 @@ Partition of: gtest_parent FOR VALUES FROM ('08-01-2016') TO ('09-01-2016') Partition of: gtest_parent FOR VALUES FROM ('09-01-2016') TO ('10-01-2016') INSERT INTO gtest_parent (f1, f2) VALUES ('2016-07-15', 1); -SELECT * FROM gtest_parent; - f1 | f2 | f3 -------------+----+---- - 07-15-2016 | 1 | 2 -(1 row) +INSERT INTO gtest_parent (f1, f2) VALUES ('2016-07-15', 2); +INSERT INTO gtest_parent (f1, f2) VALUES ('2016-08-15', 3); +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; + tableoid | f1 | f2 | f3 +--------------+------------+----+---- + gtest_child | 07-15-2016 | 1 | 2 + gtest_child | 07-15-2016 | 2 | 4 + gtest_child2 | 08-15-2016 | 3 | 66 +(3 rows) -SELECT * FROM gtest_child; - f1 | f2 | f3 -------------+----+---- - 07-15-2016 | 1 | 2 -(1 row) +UPDATE gtest_parent SET f1 = f1 + 60 WHERE f2 = 1; +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; + tableoid | f1 | f2 | f3 +--------------+------------+----+---- + gtest_child | 07-15-2016 | 2 | 4 + gtest_child2 | 08-15-2016 | 3 | 66 + gtest_child3 | 09-13-2016 | 1 | 33 +(3 rows) -UPDATE gtest_parent SET f1 = f1 + 60; -SELECT * FROM gtest_parent; - f1 | f2 | f3 -------------+----+---- - 09-13-2016 | 1 | 33 -(1 row) +-- alter only parent's and one child's generated expression +ALTER TABLE ONLY gtest_parent ALTER COLUMN f3 SET EXPRESSION AS (f2 * 4); +ALTER TABLE gtest_child ALTER COLUMN f3 SET EXPRESSION AS (f2 * 10); +\d gtest_parent + Partitioned table "public.gtest_parent" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 4) stored +Partition key: RANGE (f1) +Number of partitions: 3 (Use \d+ to list them.) -SELECT * FROM gtest_child3; - f1 | f2 | f3 -------------+----+---- - 09-13-2016 | 1 | 33 -(1 row) +\d gtest_child + Table "public.gtest_child" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+-------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 10) stored +Partition of: gtest_parent FOR VALUES FROM ('07-01-2016') TO ('08-01-2016') + +\d gtest_child2 + Table "public.gtest_child2" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+-------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 22) stored +Partition of: gtest_parent FOR VALUES FROM ('08-01-2016') TO ('09-01-2016') + +\d gtest_child3 + Table "public.gtest_child3" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+-------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 33) stored +Partition of: gtest_parent FOR VALUES FROM ('09-01-2016') TO ('10-01-2016') + +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; + tableoid | f1 | f2 | f3 +--------------+------------+----+---- + gtest_child | 07-15-2016 | 2 | 20 + gtest_child2 | 08-15-2016 | 3 | 66 + gtest_child3 | 09-13-2016 | 1 | 33 +(3 rows) + +-- alter generated expression of a parent and all it's child altogether +ALTER TABLE gtest_parent ALTER COLUMN f3 SET EXPRESSION AS (f2 * 2); +\d gtest_parent + Partitioned table "public.gtest_parent" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 2) stored +Partition key: RANGE (f1) +Number of partitions: 3 (Use \d+ to list them.) + +\d gtest_child + Table "public.gtest_child" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 2) stored +Partition of: gtest_parent FOR VALUES FROM ('07-01-2016') TO ('08-01-2016') + +\d gtest_child2 + Table "public.gtest_child2" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 2) stored +Partition of: gtest_parent FOR VALUES FROM ('08-01-2016') TO ('09-01-2016') + +\d gtest_child3 + Table "public.gtest_child3" + Column | Type | Collation | Nullable | Default +--------+--------+-----------+----------+------------------------------------- + f1 | date | | not null | + f2 | bigint | | | + f3 | bigint | | | generated always as (f2 * 2) stored +Partition of: gtest_parent FOR VALUES FROM ('09-01-2016') TO ('10-01-2016') + +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; + tableoid | f1 | f2 | f3 +--------------+------------+----+---- + gtest_child | 07-15-2016 | 2 | 4 + gtest_child2 | 08-15-2016 | 3 | 6 + gtest_child3 | 09-13-2016 | 1 | 2 +(3 rows) -- we leave these tables around for purposes of testing dump/reload/upgrade -- generated columns in partition key (not allowed) @@ -935,18 +1024,50 @@ CREATE TABLE gtest29 ( b int GENERATED ALWAYS AS (a * 2) STORED ); INSERT INTO gtest29 (a) VALUES (3), (4); +SELECT * FROM gtest29; + a | b +---+--- + 3 | 6 + 4 | 8 +(2 rows) + +\d gtest29 + Table "public.gtest29" + Column | Type | Collation | Nullable | Default +--------+---------+-----------+----------+------------------------------------ + a | integer | | | + b | integer | | | generated always as (a * 2) stored + +ALTER TABLE gtest29 ALTER COLUMN a SET EXPRESSION AS (a * 3); -- error +ERROR: column "a" of relation "gtest29" is not a stored generated column ALTER TABLE gtest29 ALTER COLUMN a DROP EXPRESSION; -- error ERROR: column "a" of relation "gtest29" is not a stored generated column ALTER TABLE gtest29 ALTER COLUMN a DROP EXPRESSION IF EXISTS; -- notice NOTICE: column "a" of relation "gtest29" is not a stored generated column, skipping +-- Change the expression +ALTER TABLE gtest29 ALTER COLUMN b SET EXPRESSION AS (a * 3); +SELECT * FROM gtest29; + a | b +---+---- + 3 | 9 + 4 | 12 +(2 rows) + +\d gtest29 + Table "public.gtest29" + Column | Type | Collation | Nullable | Default +--------+---------+-----------+----------+------------------------------------ + a | integer | | | + b | integer | | | generated always as (a * 3) stored + ALTER TABLE gtest29 ALTER COLUMN b DROP EXPRESSION; INSERT INTO gtest29 (a) VALUES (5); INSERT INTO gtest29 (a, b) VALUES (6, 66); SELECT * FROM gtest29; a | b ---+---- - 3 | 6 - 4 | 8 + 3 | 9 + 4 | 12 5 | 6 | 66 (4 rows) diff --git a/src/test/regress/sql/generated.sql b/src/test/regress/sql/generated.sql index 298f6b3aa8b..a0a1942056b 100644 --- a/src/test/regress/sql/generated.sql +++ b/src/test/regress/sql/generated.sql @@ -414,11 +414,28 @@ ALTER TABLE gtest_parent ATTACH PARTITION gtest_child3 FOR VALUES FROM ('2016-09 \d gtest_child2 \d gtest_child3 INSERT INTO gtest_parent (f1, f2) VALUES ('2016-07-15', 1); -SELECT * FROM gtest_parent; -SELECT * FROM gtest_child; -UPDATE gtest_parent SET f1 = f1 + 60; -SELECT * FROM gtest_parent; -SELECT * FROM gtest_child3; +INSERT INTO gtest_parent (f1, f2) VALUES ('2016-07-15', 2); +INSERT INTO gtest_parent (f1, f2) VALUES ('2016-08-15', 3); +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; +UPDATE gtest_parent SET f1 = f1 + 60 WHERE f2 = 1; +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; + +-- alter only parent's and one child's generated expression +ALTER TABLE ONLY gtest_parent ALTER COLUMN f3 SET EXPRESSION AS (f2 * 4); +ALTER TABLE gtest_child ALTER COLUMN f3 SET EXPRESSION AS (f2 * 10); +\d gtest_parent +\d gtest_child +\d gtest_child2 +\d gtest_child3 +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; + +-- alter generated expression of a parent and all it's child altogether +ALTER TABLE gtest_parent ALTER COLUMN f3 SET EXPRESSION AS (f2 * 2); +\d gtest_parent +\d gtest_child +\d gtest_child2 +\d gtest_child3 +SELECT tableoid::regclass, * FROM gtest_parent ORDER BY 1, 2, 3; -- we leave these tables around for purposes of testing dump/reload/upgrade -- generated columns in partition key (not allowed) @@ -473,8 +490,17 @@ CREATE TABLE gtest29 ( b int GENERATED ALWAYS AS (a * 2) STORED ); INSERT INTO gtest29 (a) VALUES (3), (4); +SELECT * FROM gtest29; +\d gtest29 +ALTER TABLE gtest29 ALTER COLUMN a SET EXPRESSION AS (a * 3); -- error ALTER TABLE gtest29 ALTER COLUMN a DROP EXPRESSION; -- error ALTER TABLE gtest29 ALTER COLUMN a DROP EXPRESSION IF EXISTS; -- notice + +-- Change the expression +ALTER TABLE gtest29 ALTER COLUMN b SET EXPRESSION AS (a * 3); +SELECT * FROM gtest29; +\d gtest29 + ALTER TABLE gtest29 ALTER COLUMN b DROP EXPRESSION; INSERT INTO gtest29 (a) VALUES (5); INSERT INTO gtest29 (a, b) VALUES (6, 66); -- 2.18.0