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Diffstat (limited to 'src/backend/commands/tablecmds.c')
-rw-r--r--src/backend/commands/tablecmds.c196
1 files changed, 158 insertions, 38 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 18f64db6e39..94660e4bd45 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -3039,6 +3039,15 @@ MergeAttributes(List *columns, const List *supers, char relpersistence,
errhint("A child table column cannot be generated unless its parent column is.")));
}
+ if (coldef->generated && restdef->generated && coldef->generated != restdef->generated)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_COLUMN_DEFINITION),
+ errmsg("column \"%s\" inherits from generated column of different kind",
+ restdef->colname),
+ errdetail("Parent column is %s, child column is %s.",
+ coldef->generated == ATTRIBUTE_GENERATED_STORED ? "STORED" : "VIRTUAL",
+ restdef->generated == ATTRIBUTE_GENERATED_STORED ? "STORED" : "VIRTUAL")));
+
/*
* Override the parent's default value for this column
* (coldef->cooked_default) with the partition's local
@@ -3324,6 +3333,15 @@ MergeChildAttribute(List *inh_columns, int exist_attno, int newcol_attno, const
errhint("A child table column cannot be generated unless its parent column is.")));
}
+ if (inhdef->generated && newdef->generated && newdef->generated != inhdef->generated)
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_COLUMN_DEFINITION),
+ errmsg("column \"%s\" inherits from generated column of different kind",
+ inhdef->colname),
+ errdetail("Parent column is %s, child column is %s.",
+ inhdef->generated == ATTRIBUTE_GENERATED_STORED ? "STORED" : "VIRTUAL",
+ newdef->generated == ATTRIBUTE_GENERATED_STORED ? "STORED" : "VIRTUAL")));
+
/*
* If new def has a default, override previous default
*/
@@ -6130,7 +6148,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap)
{
case CONSTR_CHECK:
needscan = true;
- con->qualstate = ExecPrepareExpr((Expr *) con->qual, estate);
+ con->qualstate = ExecPrepareExpr((Expr *) expand_generated_columns_in_expr(con->qual, newrel ? newrel : oldrel, 1), estate);
break;
case CONSTR_FOREIGN:
/* Nothing to do here */
@@ -7308,7 +7326,7 @@ ATExecAddColumn(List **wqueue, AlteredTableInfo *tab, Relation rel,
* DEFAULT value outside of the heap. This may be disabled inside
* AddRelationNewConstraints if the optimization cannot be applied.
*/
- rawEnt->missingMode = (!colDef->generated);
+ rawEnt->missingMode = (colDef->generated != ATTRIBUTE_GENERATED_STORED);
rawEnt->generated = colDef->generated;
@@ -7785,6 +7803,14 @@ ATExecSetNotNull(List **wqueue, Relation rel, char *conName, char *colName,
errmsg("cannot alter system column \"%s\"",
colName)));
+ /* TODO: see transformColumnDefinition() */
+ if (TupleDescAttr(RelationGetDescr(rel), attnum - 1)->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("not-null constraints are not supported on virtual generated columns"),
+ errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.",
+ colName, RelationGetRelationName(rel))));
+
/* See if there's already a constraint */
tuple = findNotNullConstraintAttnum(RelationGetRelid(rel), attnum);
if (HeapTupleIsValid(tuple))
@@ -8411,6 +8437,8 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName,
HeapTuple tuple;
Form_pg_attribute attTup;
AttrNumber attnum;
+ char attgenerated;
+ bool rewrite;
Oid attrdefoid;
ObjectAddress address;
Expr *defval;
@@ -8425,36 +8453,70 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName,
colName, RelationGetRelationName(rel))));
attTup = (Form_pg_attribute) GETSTRUCT(tuple);
- attnum = attTup->attnum;
+ 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)
+ attgenerated = attTup->attgenerated;
+ if (!attgenerated)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
errmsg("column \"%s\" of relation \"%s\" is not a generated column",
colName, RelationGetRelationName(rel))));
- ReleaseSysCache(tuple);
/*
- * Clear all the missing values if we're rewriting the table, since this
- * renders them pointless.
+ * TODO: This could be done, just need to recheck any constraints
+ * afterwards.
*/
- RelationClearMissing(rel);
-
- /* make sure we don't conflict with later attribute modifications */
- CommandCounterIncrement();
+ if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL &&
+ rel->rd_att->constr && rel->rd_att->constr->num_check > 0)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("ALTER TABLE / SET EXPRESSION is not supported for virtual generated columns on tables with check constraints"),
+ errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.",
+ colName, RelationGetRelationName(rel))));
/*
- * Find everything that depends on the column (constraints, indexes, etc),
- * and record enough information to let us recreate the objects after
- * rewrite.
+ * We need to prevent this because a change of expression could affect a
+ * row filter and inject expressions that are not permitted in a row
+ * filter. XXX We could try to have a more precise check to catch only
+ * publications with row filters, or even re-verify the row filter
+ * expressions.
*/
- RememberAllDependentForRebuilding(tab, AT_SetExpression, rel, attnum, colName);
+ if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL &&
+ GetRelationPublications(RelationGetRelid(rel)) != NIL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("ALTER TABLE / SET EXPRESSION is not supported for virtual generated columns on tables that are part of a publication"),
+ errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.",
+ colName, RelationGetRelationName(rel))));
+
+ rewrite = (attgenerated == ATTRIBUTE_GENERATED_STORED);
+
+ ReleaseSysCache(tuple);
+
+ if (rewrite)
+ {
+ /*
+ * Clear all the missing values if we're rewriting the table, since
+ * this renders them pointless.
+ */
+ RelationClearMissing(rel);
+
+ /* make sure we don't conflict with later attribute modifications */
+ CommandCounterIncrement();
+
+ /*
+ * Find everything that depends on the column (constraints, indexes,
+ * etc), and record enough information to let us recreate the objects
+ * after rewrite.
+ */
+ RememberAllDependentForRebuilding(tab, AT_SetExpression, rel, attnum, colName);
+ }
/*
* Drop the dependency records of the GENERATED expression, in particular
@@ -8483,7 +8545,7 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName,
rawEnt->attnum = attnum;
rawEnt->raw_default = newExpr;
rawEnt->missingMode = false;
- rawEnt->generated = ATTRIBUTE_GENERATED_STORED;
+ rawEnt->generated = attgenerated;
/* Store the generated expression */
AddRelationNewConstraints(rel, list_make1(rawEnt), NIL,
@@ -8492,16 +8554,19 @@ ATExecSetExpression(AlteredTableInfo *tab, Relation rel, const char *colName,
/* Make above new expression visible */
CommandCounterIncrement();
- /* Prepare for table rewrite */
- defval = (Expr *) build_column_default(rel, attnum);
+ if (rewrite)
+ {
+ /* 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;
+ 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;
+ tab->newvals = lappend(tab->newvals, newval);
+ tab->rewrite |= AT_REWRITE_DEFAULT_VAL;
+ }
/* Drop any pg_statistic entry for the column */
RemoveStatistics(RelationGetRelid(rel), attnum);
@@ -8590,17 +8655,30 @@ ATExecDropExpression(Relation rel, const char *colName, bool missing_ok, LOCKMOD
errmsg("cannot alter system column \"%s\"",
colName)));
- if (attTup->attgenerated != ATTRIBUTE_GENERATED_STORED)
+ /*
+ * TODO: This could be done, but it would need a table rewrite to
+ * materialize the generated values. Note that for the time being, we
+ * still error with missing_ok, so that we don't silently leave the column
+ * as generated.
+ */
+ if (attTup->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("ALTER TABLE / DROP EXPRESSION is not supported for virtual generated columns"),
+ errdetail("Column \"%s\" of relation \"%s\" is a virtual generated column.",
+ colName, RelationGetRelationName(rel))));
+
+ if (!attTup->attgenerated)
{
if (!missing_ok)
ereport(ERROR,
(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
- errmsg("column \"%s\" of relation \"%s\" is not a stored generated column",
+ errmsg("column \"%s\" of relation \"%s\" is not a generated column",
colName, RelationGetRelationName(rel))));
else
{
ereport(NOTICE,
- (errmsg("column \"%s\" of relation \"%s\" is not a stored generated column, skipping",
+ (errmsg("column \"%s\" of relation \"%s\" is not a generated column, skipping",
colName, RelationGetRelationName(rel))));
heap_freetuple(tuple);
table_close(attrelation, RowExclusiveLock);
@@ -8743,6 +8821,16 @@ ATExecSetStatistics(Relation rel, const char *colName, int16 colNum, Node *newVa
errmsg("cannot alter system column \"%s\"",
colName)));
+ /*
+ * Prevent this as long as the ANALYZE code skips virtual generated
+ * columns.
+ */
+ if (attrtuple->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot alter statistics on virtual generated column \"%s\"",
+ colName)));
+
if (rel->rd_rel->relkind == RELKIND_INDEX ||
rel->rd_rel->relkind == RELKIND_PARTITIONED_INDEX)
{
@@ -9925,6 +10013,19 @@ ATAddForeignKeyConstraint(List **wqueue, AlteredTableInfo *tab, Relation rel,
errmsg("invalid %s action for foreign key constraint containing generated column",
"ON DELETE")));
}
+
+ /*
+ * FKs on virtual columns are not supported. This would require
+ * various additional support in ri_triggers.c, including special
+ * handling in ri_NullCheck(), ri_KeysEqual(),
+ * RI_FKey_fk_upd_check_required() (since all virtual columns appear
+ * as NULL there). Also not really practical as long as you can't
+ * index virtual columns.
+ */
+ if (attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("foreign key constraints on virtual generated columns are not supported")));
}
/*
@@ -12289,7 +12390,7 @@ QueueCheckConstraintValidation(List **wqueue, Relation conrel, Relation rel,
val = SysCacheGetAttrNotNull(CONSTROID, contuple,
Anum_pg_constraint_conbin);
conbin = TextDatumGetCString(val);
- newcon->qual = (Node *) stringToNode(conbin);
+ newcon->qual = expand_generated_columns_in_expr(stringToNode(conbin), rel, 1);
/* Find or create work queue entry for this table */
tab = ATGetQueueEntry(wqueue, rel);
@@ -13467,8 +13568,12 @@ ATPrepAlterColumnType(List **wqueue,
list_make1_oid(rel->rd_rel->reltype),
0);
- if (tab->relkind == RELKIND_RELATION ||
- tab->relkind == RELKIND_PARTITIONED_TABLE)
+ if (attTup->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
+ {
+ /* do nothing */
+ }
+ else if (tab->relkind == RELKIND_RELATION ||
+ tab->relkind == RELKIND_PARTITIONED_TABLE)
{
/*
* Set up an expression to transform the old data value to the new
@@ -13541,11 +13646,12 @@ ATPrepAlterColumnType(List **wqueue,
errmsg("\"%s\" is not a table",
RelationGetRelationName(rel))));
- if (!RELKIND_HAS_STORAGE(tab->relkind))
+ if (!RELKIND_HAS_STORAGE(tab->relkind) || attTup->attgenerated == ATTRIBUTE_GENERATED_VIRTUAL)
{
/*
- * For relations without storage, do this check now. Regular tables
- * will check it later when the table is being rewritten.
+ * For relations or columns without storage, do this check now.
+ * Regular tables will check it later when the table is being
+ * rewritten.
*/
find_composite_type_dependencies(rel->rd_rel->reltype, rel, NULL);
}
@@ -16534,6 +16640,14 @@ MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel, bool ispart
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("column \"%s\" in child table must not be a generated column", parent_attname)));
+ if (parent_att->attgenerated && child_att->attgenerated && child_att->attgenerated != parent_att->attgenerated)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("column \"%s\" inherits from generated column of different kind", parent_attname),
+ errdetail("Parent column is %s, child column is %s.",
+ parent_att->attgenerated == ATTRIBUTE_GENERATED_STORED ? "STORED" : "VIRTUAL",
+ child_att->attgenerated == ATTRIBUTE_GENERATED_STORED ? "STORED" : "VIRTUAL")));
+
/*
* Regular inheritance children are independent enough not to
* inherit identity columns. But partitions are integral part of
@@ -18781,8 +18895,11 @@ ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNu
parser_errposition(pstate, pelem->location)));
/*
- * Generated columns cannot work: They are computed after BEFORE
- * triggers, but partition routing is done before all triggers.
+ * Stored generated columns cannot work: They are computed after
+ * BEFORE triggers, but partition routing is done before all
+ * triggers. Maybe virtual generated columns could be made to
+ * work, but then they would need to be handled as an expression
+ * below.
*/
if (attform->attgenerated)
ereport(ERROR,
@@ -18864,9 +18981,12 @@ ComputePartitionAttrs(ParseState *pstate, Relation rel, List *partParams, AttrNu
}
/*
- * Generated columns cannot work: They are computed after
- * BEFORE triggers, but partition routing is done before all
- * triggers.
+ * Stored generated columns cannot work: They are computed
+ * after BEFORE triggers, but partition routing is done before
+ * all triggers. Virtual generated columns could probably
+ * work, but it would require more work elsewhere (for example
+ * SET EXPRESSION would need to check whether the column is
+ * used in partition keys). Seems safer to prohibit for now.
*/
i = -1;
while ((i = bms_next_member(expr_attrs, i)) >= 0)
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-20 12:31:45 +0000