/*
* create_ctas_nodata
*
* Create CTAS or materialized view when WITH NO DATA is used, starting from
* the targetlist of the SELECT or view definition.
*/
static ObjectAddress
create_ctas_nodata(List *tlist, IntoClause *into)
{
List *attrList;
ListCell *t,
*lc;
/*
* Build list of ColumnDefs from non-junk elements of the tlist. If a
* column name list was specified in CREATE TABLE AS, override the column
* names in the query. (Too few column names are OK, too many are not.)
*/
attrList = NIL;
lc = list_head(into->colNames);
foreach(t, tlist)
{
TargetEntry *tle = (TargetEntry *) lfirst(t);
if (!tle->resjunk)
{
ColumnDef *col;
char *colname;
if (lc)
{
colname = strVal(lfirst(lc));
lc = lnext(lc);
}
else
colname = tle->resname;
col = makeColumnDef(colname,
exprType((Node *) tle->expr),
exprTypmod((Node *) tle->expr),
exprCollation((Node *) tle->expr));
/*
* It's possible that the column is of a collatable type but the
* collation could not be resolved, so double-check. (We must
* check this here because DefineRelation would adopt the type's
* default collation rather than complaining.)
*/
if (!OidIsValid(col->collOid) &&
type_is_collatable(col->typeName->typeOid))
ereport(ERROR,
(errcode(ERRCODE_INDETERMINATE_COLLATION),
errmsg("no collation was derived for column \"%s\" with collatable type %s",
col->colname,
format_type_be(col->typeName->typeOid)),
errhint("Use the COLLATE clause to set the collation explicitly.")));
attrList = lappend(attrList, col);
}
}
/*---------------------------------------------------------------------
* DefineVirtualRelation
*
* Create the "view" relation. `DefineRelation' does all the work,
* we just provide the correct arguments ... at least when we're
* creating a view. If we're updating an existing view, we have to
* work harder.
*---------------------------------------------------------------------
*/
static ObjectAddress
DefineVirtualRelation(RangeVar *relation, List *tlist, bool replace,
List *options)
{
Oid viewOid;
LOCKMODE lockmode;
CreateStmt *createStmt = makeNode(CreateStmt);
List *attrList;
ListCell *t;
/*
* create a list of ColumnDef nodes based on the names and types of the
* (non-junk) targetlist items from the view's SELECT list.
*/
attrList = NIL;
foreach(t, tlist)
{
TargetEntry *tle = (TargetEntry *) lfirst(t);
if (!tle->resjunk)
{
ColumnDef *def = makeColumnDef(tle->resname,
exprType((Node *) tle->expr),
exprTypmod((Node *) tle->expr),
exprCollation((Node *) tle->expr));
/*
* It's possible that the column is of a collatable type but the
* collation could not be resolved, so double-check.
*/
if (type_is_collatable(exprType((Node *) tle->expr)))
{
if (!OidIsValid(def->collOid))
ereport(ERROR,
(errcode(ERRCODE_INDETERMINATE_COLLATION),
errmsg("could not determine which collation to use for view column \"%s\"",
def->colname),
errhint("Use the COLLATE clause to set the collation explicitly.")));
}
else
Assert(!OidIsValid(def->collOid));
attrList = lappend(attrList, def);
}
}
