diff options
Diffstat (limited to 'src/backend/commands/tablecmds.c')
| -rw-r--r-- | src/backend/commands/tablecmds.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 6f4a3e70a40..d6785192840 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -13433,6 +13433,66 @@ MergeAttributesIntoExisting(Relation child_rel, Relation parent_rel) attributeName))); /* + * If parent column is generated, child column must be, too. + */ + if (attribute->attgenerated && !childatt->attgenerated) + ereport(ERROR, + (errcode(ERRCODE_DATATYPE_MISMATCH), + errmsg("column \"%s\" in child table must be a generated column", + attributeName))); + + /* + * Check that both generation expressions match. + * + * The test we apply is to see whether they reverse-compile to the + * same source string. This insulates us from issues like whether + * attributes have the same physical column numbers in parent and + * child relations. (See also constraints_equivalent().) + */ + if (attribute->attgenerated && childatt->attgenerated) + { + TupleConstr *child_constr = child_rel->rd_att->constr; + TupleConstr *parent_constr = parent_rel->rd_att->constr; + char *child_expr = NULL; + char *parent_expr = NULL; + + Assert(child_constr != NULL); + Assert(parent_constr != NULL); + + for (int i = 0; i < child_constr->num_defval; i++) + { + if (child_constr->defval[i].adnum == childatt->attnum) + { + child_expr = + TextDatumGetCString(DirectFunctionCall2(pg_get_expr, + CStringGetTextDatum(child_constr->defval[i].adbin), + ObjectIdGetDatum(child_rel->rd_id))); + break; + } + } + Assert(child_expr != NULL); + + for (int i = 0; i < parent_constr->num_defval; i++) + { + if (parent_constr->defval[i].adnum == attribute->attnum) + { + parent_expr = + TextDatumGetCString(DirectFunctionCall2(pg_get_expr, + CStringGetTextDatum(parent_constr->defval[i].adbin), + ObjectIdGetDatum(parent_rel->rd_id))); + break; + } + } + Assert(parent_expr != NULL); + + if (strcmp(child_expr, parent_expr) != 0) + ereport(ERROR, + (errcode(ERRCODE_DATATYPE_MISMATCH), + errmsg("column \"%s\" in child table has a conflicting generation expression", + attributeName))); + } + + /* * OK, bump the child column's inheritance count. (If we fail * later on, this change will just roll back.) */ |