Datum
pg_relation_size_name(PG_FUNCTION_ARGS)
{
text *relname = PG_GETARG_TEXT_P(0);
RangeVar *relrv;
Relation rel;
int64 size;
if (GP_ROLE_EXECUTE == Gp_role)
{
ereport(ERROR,
(errcode(ERRCODE_GP_COMMAND_ERROR),
errmsg("pg_relation_size: cannot be executed in segment")));
}
relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
rel = try_relation_openrv(relrv, AccessShareLock, false);
/*
* While we scan pg_class with an MVCC snapshot,
* someone else might drop the table. It's better to return NULL for
* already-dropped tables than throw an error and abort the whole query.
*/
if (!RelationIsValid(rel))
PG_RETURN_NULL();
if (rel->rd_node.relNode == 0)
size = 0;
else
size = calculate_relation_size(rel);
relation_close(rel, AccessShareLock);
PG_RETURN_INT64(size);
}
Datum
pg_relation_size_name(PG_FUNCTION_ARGS)
{
text *relname = PG_GETARG_TEXT_P(0);
RangeVar *relrv;
Relation rel;
int64 size;
/**
* This function is peculiar in that it does its own dispatching.
* It does not work on entry db since we do not support dispatching
* from entry-db currently.
*/
if (Gp_role == GP_ROLE_EXECUTE && Gp_segment == -1)
{
elog(ERROR, "This query is not currently supported by GPDB.");
}
relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
if (Gp_role == GP_ROLE_EXECUTE && relrv->schemaname != NULL)
{
Oid namespaceId;
Oid relOid;
/*
* Do this the hard way, because the optimizer wants to be
* able to use this function on relations the user might not
* have direct access to.
*/
AcceptInvalidationMessages();
namespaceId = caql_getoid(
NULL,
cql("SELECT oid FROM pg_namespace "
" WHERE nspname = :1 ",
CStringGetDatum(relrv->schemaname)));
relOid = get_relname_relid(relrv->relname, namespaceId);
if (!OidIsValid(relOid))
{
size = 0;
PG_RETURN_INT64(size);
}
/* Let relation_open do the rest */
rel = try_relation_open(relOid, AccessShareLock, false);
}
else
rel = try_relation_openrv(relrv, AccessShareLock, false);
/*
* While we scan pg_class with an MVCC snapshot,
* someone else might drop the table. It's better to return NULL for
* already-dropped tables than throw an error and abort the whole query.
*/
if (!RelationIsValid(rel))
PG_RETURN_NULL();
if (rel->rd_node.relNode == 0)
size = 0;
else
size = calculate_relation_size(rel);
if (Gp_role == GP_ROLE_DISPATCH)
{
char * rawname;
StringInfoData buffer;
initStringInfo(&buffer);
rawname = DatumGetCString(DirectFunctionCall1(textout,
PointerGetDatum(relname)));
initStringInfo(&buffer);
appendStringInfo(&buffer, "select sum(pg_relation_size('%s'))::int8 from gp_dist_random('gp_id');", rawname);
size += get_size_from_segDBs(buffer.data);
}
relation_close(rel, AccessShareLock);
PG_RETURN_INT64(size);
}
