/*
* ExecRefreshMatView -- execute a REFRESH MATERIALIZED VIEW command
*
* This refreshes the materialized view by creating a new table and swapping
* the relfilenodes of the new table and the old materialized view, so the OID
* of the original materialized view is preserved. Thus we do not lose GRANT
* nor references to this materialized view.
*
* If WITH NO DATA was specified, this is effectively like a TRUNCATE;
* otherwise it is like a TRUNCATE followed by an INSERT using the SELECT
* statement associated with the materialized view. The statement node's
* skipData field shows whether the clause was used.
*
* Indexes are rebuilt too, via REINDEX. Since we are effectively bulk-loading
* the new heap, it's better to create the indexes afterwards than to fill them
* incrementally while we load.
*
* The matview's "populated" state is changed based on whether the contents
* reflect the result set of the materialized view's query.
*/
void
ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
ParamListInfo params, char *completionTag)
{
Oid matviewOid;
Relation matviewRel;
RewriteRule *rule;
List *actions;
Query *dataQuery;
Oid tableSpace;
Oid relowner;
Oid OIDNewHeap;
DestReceiver *dest;
bool concurrent;
LOCKMODE lockmode;
Oid save_userid;
int save_sec_context;
int save_nestlevel;
/* Determine strength of lock needed. */
concurrent = stmt->concurrent;
lockmode = concurrent ? ExclusiveLock : AccessExclusiveLock;
/*
* Get a lock until end of transaction.
*/
matviewOid = RangeVarGetRelidExtended(stmt->relation,
lockmode, false, false,
RangeVarCallbackOwnsTable, NULL);
matviewRel = heap_open(matviewOid, NoLock);
/* Make sure it is a materialized view. */
if (matviewRel->rd_rel->relkind != RELKIND_MATVIEW)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("\"%s\" is not a materialized view",
RelationGetRelationName(matviewRel))));
/* Check that CONCURRENTLY is not specified if not populated. */
if (concurrent && !RelationIsPopulated(matviewRel))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("CONCURRENTLY cannot be used when the materialized view is not populated")));
/* Check that conflicting options have not been specified. */
if (concurrent && stmt->skipData)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("CONCURRENTLY and WITH NO DATA options cannot be used together")));
/* We don't allow an oid column for a materialized view. */
Assert(!matviewRel->rd_rel->relhasoids);
/*
* Check that everything is correct for a refresh. Problems at this point
* are internal errors, so elog is sufficient.
*/
if (matviewRel->rd_rel->relhasrules == false ||
matviewRel->rd_rules->numLocks < 1)
elog(ERROR,
"materialized view \"%s\" is missing rewrite information",
RelationGetRelationName(matviewRel));
if (matviewRel->rd_rules->numLocks > 1)
elog(ERROR,
"materialized view \"%s\" has too many rules",
RelationGetRelationName(matviewRel));
rule = matviewRel->rd_rules->rules[0];
if (rule->event != CMD_SELECT || !(rule->isInstead))
elog(ERROR,
"the rule for materialized view \"%s\" is not a SELECT INSTEAD OF rule",
RelationGetRelationName(matviewRel));
actions = rule->actions;
if (list_length(actions) != 1)
elog(ERROR,
"the rule for materialized view \"%s\" is not a single action",
RelationGetRelationName(matviewRel));
/*
* The stored query was rewritten at the time of the MV definition, but
* has not been scribbled on by the planner.
*/
dataQuery = (Query *) linitial(actions);
Assert(IsA(dataQuery, Query));
/*
* Check for active uses of the relation in the current transaction, such
* as open scans.
*
* NB: We count on this to protect us against problems with refreshing the
* data using HEAP_INSERT_FROZEN.
*/
CheckTableNotInUse(matviewRel, "REFRESH MATERIALIZED VIEW");
/*
* Tentatively mark the matview as populated or not (this will roll back
* if we fail later).
*/
SetMatViewPopulatedState(matviewRel, !stmt->skipData);
relowner = matviewRel->rd_rel->relowner;
/*
* Switch to the owner's userid, so that any functions are run as that
* user. Also arrange to make GUC variable changes local to this command.
* Don't lock it down too tight to create a temporary table just yet. We
* will switch modes when we are about to execute user code.
*/
GetUserIdAndSecContext(&save_userid, &save_sec_context);
SetUserIdAndSecContext(relowner,
save_sec_context | SECURITY_LOCAL_USERID_CHANGE);
save_nestlevel = NewGUCNestLevel();
/* Concurrent refresh builds new data in temp tablespace, and does diff. */
if (concurrent)
tableSpace = GetDefaultTablespace(RELPERSISTENCE_TEMP);
else
tableSpace = matviewRel->rd_rel->reltablespace;
/*
* Create the transient table that will receive the regenerated data. Lock
* it against access by any other process until commit (by which time it
* will be gone).
*/
OIDNewHeap = make_new_heap(matviewOid, tableSpace, concurrent,
ExclusiveLock);
LockRelationOid(OIDNewHeap, AccessExclusiveLock);
dest = CreateTransientRelDestReceiver(OIDNewHeap);
/*
* Now lock down security-restricted operations.
*/
SetUserIdAndSecContext(relowner,
save_sec_context | SECURITY_RESTRICTED_OPERATION);
/* Generate the data, if wanted. */
if (!stmt->skipData)
refresh_matview_datafill(dest, dataQuery, queryString);
heap_close(matviewRel, NoLock);
/* Make the matview match the newly generated data. */
if (concurrent)
{
int old_depth = matview_maintenance_depth;
PG_TRY();
{
refresh_by_match_merge(matviewOid, OIDNewHeap, relowner,
save_sec_context);
}
PG_CATCH();
{
matview_maintenance_depth = old_depth;
PG_RE_THROW();
}
PG_END_TRY();
Assert(matview_maintenance_depth == old_depth);
}
else
refresh_by_heap_swap(matviewOid, OIDNewHeap);
/* Roll back any GUC changes */
AtEOXact_GUC(false, save_nestlevel);
/* Restore userid and security context */
SetUserIdAndSecContext(save_userid, save_sec_context);
}
/*
* intorel_startup --- executor startup
*/
static void
intorel_startup(DestReceiver *self, int operation, TupleDesc typeinfo)
{
DR_intorel *myState = (DR_intorel *) self;
IntoClause *into = myState->into;
bool is_matview;
char relkind;
CreateStmt *create;
Oid intoRelationId;
Relation intoRelationDesc;
RangeTblEntry *rte;
Datum toast_options;
ListCell *lc;
int attnum;
static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
Assert(into != NULL); /* else somebody forgot to set it */
/* This code supports both CREATE TABLE AS and CREATE MATERIALIZED VIEW */
is_matview = (into->viewQuery != NULL);
relkind = is_matview ? RELKIND_MATVIEW : RELKIND_RELATION;
/*
* Create the target relation by faking up a CREATE TABLE parsetree and
* passing it to DefineRelation.
*/
create = makeNode(CreateStmt);
create->relation = into->rel;
create->tableElts = NIL; /* will fill below */
create->inhRelations = NIL;
create->ofTypename = NULL;
create->constraints = NIL;
create->options = into->options;
create->oncommit = into->onCommit;
create->tablespacename = into->tableSpaceName;
create->if_not_exists = false;
/*
* Build column definitions using "pre-cooked" type and collation info. If
* a column name list was specified in CREATE TABLE AS, override the
* column names derived from the query. (Too few column names are OK, too
* many are not.)
*/
lc = list_head(into->colNames);
for (attnum = 0; attnum < typeinfo->natts; attnum++)
{
Form_pg_attribute attribute = typeinfo->attrs[attnum];
ColumnDef *col = makeNode(ColumnDef);
TypeName *coltype = makeNode(TypeName);
if (lc)
{
col->colname = strVal(lfirst(lc));
lc = lnext(lc);
}
else
col->colname = NameStr(attribute->attname);
col->typeName = coltype;
col->inhcount = 0;
col->is_local = true;
col->is_not_null = false;
col->is_from_type = false;
col->storage = 0;
col->raw_default = NULL;
col->cooked_default = NULL;
col->collClause = NULL;
col->collOid = attribute->attcollation;
col->constraints = NIL;
col->fdwoptions = NIL;
coltype->names = NIL;
coltype->typeOid = attribute->atttypid;
coltype->setof = false;
coltype->pct_type = false;
coltype->typmods = NIL;
coltype->typemod = attribute->atttypmod;
coltype->arrayBounds = NIL;
coltype->location = -1;
/*
* 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(coltype->typeOid))
ereport(ERROR,
(errcode(ERRCODE_INDETERMINATE_COLLATION),
errmsg("no collation was derived for column \"%s\" with collatable type %s",
col->colname, format_type_be(coltype->typeOid)),
errhint("Use the COLLATE clause to set the collation explicitly.")));
create->tableElts = lappend(create->tableElts, col);
}
if (lc != NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("too many column names were specified")));
/*
* Actually create the target table
*/
intoRelationId = DefineRelation(create, relkind, InvalidOid);
/*
* If necessary, create a TOAST table for the target table. Note that
* AlterTableCreateToastTable ends with CommandCounterIncrement(), so that
* the TOAST table will be visible for insertion.
*/
CommandCounterIncrement();
/* parse and validate reloptions for the toast table */
toast_options = transformRelOptions((Datum) 0,
create->options,
"toast",
validnsps,
true, false);
(void) heap_reloptions(RELKIND_TOASTVALUE, toast_options, true);
AlterTableCreateToastTable(intoRelationId, toast_options);
/* Create the "view" part of a materialized view. */
if (is_matview)
{
/* StoreViewQuery scribbles on tree, so make a copy */
Query *query = (Query *) copyObject(into->viewQuery);
StoreViewQuery(intoRelationId, query, false);
CommandCounterIncrement();
}
/*
* Finally we can open the target table
*/
intoRelationDesc = heap_open(intoRelationId, AccessExclusiveLock);
/*
* Check INSERT permission on the constructed table.
*
* XXX: It would arguably make sense to skip this check if into->skipData
* is true.
*/
rte = makeNode(RangeTblEntry);
rte->rtekind = RTE_RELATION;
rte->relid = intoRelationId;
rte->relkind = relkind;
rte->requiredPerms = ACL_INSERT;
for (attnum = 1; attnum <= intoRelationDesc->rd_att->natts; attnum++)
rte->modifiedCols = bms_add_member(rte->modifiedCols,
attnum - FirstLowInvalidHeapAttributeNumber);
ExecCheckRTPerms(list_make1(rte), true);
/*
* Tentatively mark the target as populated, if it's a matview and we're
* going to fill it; otherwise, no change needed.
*/
if (is_matview && !into->skipData)
SetMatViewPopulatedState(intoRelationDesc, true);
/*
* Fill private fields of myState for use by later routines
*/
myState->rel = intoRelationDesc;
myState->output_cid = GetCurrentCommandId(true);
/*
* We can skip WAL-logging the insertions, unless PITR or streaming
* replication is in use. We can skip the FSM in any case.
*/
myState->hi_options = HEAP_INSERT_SKIP_FSM |
(XLogIsNeeded() ? 0 : HEAP_INSERT_SKIP_WAL);
myState->bistate = GetBulkInsertState();
/* Not using WAL requires smgr_targblock be initially invalid */
Assert(RelationGetTargetBlock(intoRelationDesc) == InvalidBlockNumber);
}
/*
* ExecRefreshMatView -- execute a REFRESH MATERIALIZED VIEW command
*
* This refreshes the materialized view by creating a new table and swapping
* the relfilenodes of the new table and the old materialized view, so the OID
* of the original materialized view is preserved. Thus we do not lose GRANT
* nor references to this materialized view.
*
* If WITH NO DATA was specified, this is effectively like a TRUNCATE;
* otherwise it is like a TRUNCATE followed by an INSERT using the SELECT
* statement associated with the materialized view. The statement node's
* skipData field shows whether the clause was used.
*
* Indexes are rebuilt too, via REINDEX. Since we are effectively bulk-loading
* the new heap, it's better to create the indexes afterwards than to fill them
* incrementally while we load.
*
* The matview's "populated" state is changed based on whether the contents
* reflect the result set of the materialized view's query.
*/
void
ExecRefreshMatView(RefreshMatViewStmt *stmt, const char *queryString,
ParamListInfo params, char *completionTag)
{
Oid matviewOid;
Relation matviewRel;
RewriteRule *rule;
List *actions;
Query *dataQuery;
Oid tableSpace;
Oid owner;
Oid OIDNewHeap;
DestReceiver *dest;
bool concurrent;
LOCKMODE lockmode;
/* Determine strength of lock needed. */
concurrent = stmt->concurrent;
lockmode = concurrent ? ExclusiveLock : AccessExclusiveLock;
/*
* Get a lock until end of transaction.
*/
matviewOid = RangeVarGetRelidExtended(stmt->relation,
lockmode, false, false,
RangeVarCallbackOwnsTable, NULL);
matviewRel = heap_open(matviewOid, NoLock);
/* Make sure it is a materialized view. */
if (matviewRel->rd_rel->relkind != RELKIND_MATVIEW)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("\"%s\" is not a materialized view",
RelationGetRelationName(matviewRel))));
/* Check that CONCURRENTLY is not specified if not populated. */
if (concurrent && !RelationIsPopulated(matviewRel))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("CONCURRENTLY cannot be used when the materialized view is not populated")));
/* Check that conflicting options have not been specified. */
if (concurrent && stmt->skipData)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("CONCURRENTLY and WITH NO DATA options cannot be used together")));
/* We're not using materialized views in the system catalogs. */
Assert(!IsSystemRelation(matviewRel));
/* We don't allow an oid column for a materialized view. */
Assert(!matviewRel->rd_rel->relhasoids);
/*
* Check that everything is correct for a refresh. Problems at this point
* are internal errors, so elog is sufficient.
*/
if (matviewRel->rd_rel->relhasrules == false ||
matviewRel->rd_rules->numLocks < 1)
elog(ERROR,
"materialized view \"%s\" is missing rewrite information",
RelationGetRelationName(matviewRel));
if (matviewRel->rd_rules->numLocks > 1)
elog(ERROR,
"materialized view \"%s\" has too many rules",
RelationGetRelationName(matviewRel));
rule = matviewRel->rd_rules->rules[0];
if (rule->event != CMD_SELECT || !(rule->isInstead))
elog(ERROR,
"the rule for materialized view \"%s\" is not a SELECT INSTEAD OF rule",
RelationGetRelationName(matviewRel));
actions = rule->actions;
if (list_length(actions) != 1)
elog(ERROR,
"the rule for materialized view \"%s\" is not a single action",
RelationGetRelationName(matviewRel));
/*
* The stored query was rewritten at the time of the MV definition, but
* has not been scribbled on by the planner.
*/
dataQuery = (Query *) linitial(actions);
Assert(IsA(dataQuery, Query));
/*
* Check for active uses of the relation in the current transaction, such
* as open scans.
*
* NB: We count on this to protect us against problems with refreshing the
* data using HEAP_INSERT_FROZEN.
*/
CheckTableNotInUse(matviewRel, "REFRESH MATERIALIZED VIEW");
/*
* Tentatively mark the matview as populated or not (this will roll back
* if we fail later).
*/
SetMatViewPopulatedState(matviewRel, !stmt->skipData);
/* Concurrent refresh builds new data in temp tablespace, and does diff. */
if (concurrent)
tableSpace = GetDefaultTablespace(RELPERSISTENCE_TEMP);
else
tableSpace = matviewRel->rd_rel->reltablespace;
owner = matviewRel->rd_rel->relowner;
heap_close(matviewRel, NoLock);
/* Create the transient table that will receive the regenerated data. */
OIDNewHeap = make_new_heap(matviewOid, tableSpace, concurrent,
ExclusiveLock);
dest = CreateTransientRelDestReceiver(OIDNewHeap);
/* Generate the data, if wanted. */
if (!stmt->skipData)
refresh_matview_datafill(dest, dataQuery, queryString, owner);
/* Make the matview match the newly generated data. */
if (concurrent)
{
int old_depth = matview_maintenance_depth;
PG_TRY();
{
refresh_by_match_merge(matviewOid, OIDNewHeap);
}
PG_CATCH();
{
matview_maintenance_depth = old_depth;
PG_RE_THROW();
}
PG_END_TRY();
Assert(matview_maintenance_depth == old_depth);
}
else
refresh_by_heap_swap(matviewOid, OIDNewHeap);
}
