diff options
Diffstat (limited to 'src/backend/commands/tablecmds.c')
| -rw-r--r-- | src/backend/commands/tablecmds.c | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index b788db35cbb..89dd8dffae0 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.142 2005/01/10 20:02:20 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.143 2005/01/24 23:21:57 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -35,6 +35,7 @@ #include "commands/tablecmds.h" #include "commands/tablespace.h" #include "commands/trigger.h" +#include "commands/typecmds.h" #include "executor/executor.h" #include "lib/stringinfo.h" #include "miscadmin.h" @@ -2853,6 +2854,7 @@ ATExecAddColumn(AlteredTableInfo *tab, Relation rel, int minattnum, maxatts; HeapTuple typeTuple; + Oid typeOid; Form_pg_type tform; Expr *defval; @@ -2930,9 +2932,10 @@ ATExecAddColumn(AlteredTableInfo *tab, Relation rel, typeTuple = typenameType(colDef->typename); tform = (Form_pg_type) GETSTRUCT(typeTuple); + typeOid = HeapTupleGetOid(typeTuple); /* make sure datatype is legal for a column */ - CheckAttributeType(colDef->colname, HeapTupleGetOid(typeTuple)); + CheckAttributeType(colDef->colname, typeOid); attributeTuple = heap_addheader(Natts_pg_attribute, false, @@ -2943,7 +2946,7 @@ ATExecAddColumn(AlteredTableInfo *tab, Relation rel, attribute->attrelid = myrelid; namestrcpy(&(attribute->attname), colDef->colname); - attribute->atttypid = HeapTupleGetOid(typeTuple); + attribute->atttypid = typeOid; attribute->attstattarget = -1; attribute->attlen = tform->typlen; attribute->attcacheoff = -1; @@ -3015,11 +3018,37 @@ ATExecAddColumn(AlteredTableInfo *tab, Relation rel, * and return NULL if so, so without any modification of the tuple * data we will get the effect of NULL values in the new column. * + * An exception occurs when the new column is of a domain type: the + * domain might have a NOT NULL constraint, or a check constraint that + * indirectly rejects nulls. If there are any domain constraints then + * we construct an explicit NULL default value that will be passed through + * CoerceToDomain processing. (This is a tad inefficient, since it + * causes rewriting the table which we really don't have to do, but + * the present design of domain processing doesn't offer any simple way + * of checking the constraints more directly.) + * * Note: we use build_column_default, and not just the cooked default * returned by AddRelationRawConstraints, so that the right thing * happens when a datatype's default applies. */ defval = (Expr *) build_column_default(rel, attribute->attnum); + + if (!defval && GetDomainConstraints(typeOid) != NIL) + { + Oid basetype = getBaseType(typeOid); + + defval = (Expr *) makeNullConst(basetype); + defval = (Expr *) coerce_to_target_type(NULL, + (Node *) defval, + basetype, + typeOid, + colDef->typename->typmod, + COERCION_ASSIGNMENT, + COERCE_IMPLICIT_CAST); + if (defval == NULL) /* should not happen */ + elog(ERROR, "failed to coerce base type to domain"); + } + if (defval) { NewColumnValue *newval; |