diff options
Diffstat (limited to 'src/backend/commands/tablecmds.c')
| -rw-r--r-- | src/backend/commands/tablecmds.c | 61 |
1 files changed, 56 insertions, 5 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 2fba83504b6..a518b552b3d 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -2618,12 +2618,55 @@ MergeAttributes(List *schema, List *supers, char relpersistence, def->is_local = true; /* Merge of NOT NULL constraints = OR 'em together */ def->is_not_null |= newdef->is_not_null; + + /* + * Check for conflicts related to generated columns. + * + * If the parent column is generated, the child column must be + * unadorned and will be made a generated column. (We could + * in theory allow the child column definition specifying the + * exact same generation expression, but that's a bit + * complicated to implement and doesn't seem very useful.) We + * also check that the child column doesn't specify a default + * value or identity, which matches the rules for a single + * column in parse_util.c. + */ + if (def->generated) + { + if (newdef->generated) + ereport(ERROR, + (errcode(ERRCODE_INVALID_COLUMN_DEFINITION), + errmsg("child column \"%s\" specifies generation expression", + def->colname), + errhint("Omit the generation expression in the definition of the child table column to inherit the generation expression from the parent table."))); + if (newdef->raw_default && !newdef->generated) + ereport(ERROR, + (errcode(ERRCODE_INVALID_COLUMN_DEFINITION), + errmsg("column \"%s\" inherits from generated column but specifies default", + def->colname))); + if (newdef->identity) + ereport(ERROR, + (errcode(ERRCODE_INVALID_COLUMN_DEFINITION), + errmsg("column \"%s\" inherits from generated column but specifies identity", + def->colname))); + } + /* + * If the parent column is not generated, then take whatever + * the child column definition says. + */ + else + { + if (newdef->generated) + def->generated = newdef->generated; + } + /* If new def has a default, override previous default */ if (newdef->raw_default != NULL) { def->raw_default = newdef->raw_default; def->cooked_default = newdef->cooked_default; } + } else { @@ -2709,11 +2752,19 @@ MergeAttributes(List *schema, List *supers, char relpersistence, ColumnDef *def = lfirst(entry); if (def->cooked_default == &bogus_marker) - ereport(ERROR, - (errcode(ERRCODE_INVALID_COLUMN_DEFINITION), - errmsg("column \"%s\" inherits conflicting default values", - def->colname), - errhint("To resolve the conflict, specify a default explicitly."))); + { + if (def->generated) + ereport(ERROR, + (errcode(ERRCODE_INVALID_COLUMN_DEFINITION), + errmsg("column \"%s\" inherits conflicting generation expressions", + def->colname))); + else + ereport(ERROR, + (errcode(ERRCODE_INVALID_COLUMN_DEFINITION), + errmsg("column \"%s\" inherits conflicting default values", + def->colname), + errhint("To resolve the conflict, specify a default explicitly."))); + } } } |