static void RemoveInheritance(Relation child_rel, Relation parent_rel);
static ObjectAddress ATExecAttachPartition(List **wqueue, Relation rel,
PartitionCmd *cmd);
+static bool PartConstraintImpliedByRelConstraint(Relation scanrel,
+ List *partConstraint);
+static void ValidatePartitionConstraints(List **wqueue, Relation scanrel,
+ List *scanrel_children,
+ List *partConstraint);
static ObjectAddress ATExecDetachPartition(Relation rel, RangeVar *name);
}
}
+/*
+ * PartConstraintImpliedByRelConstraint
+ * Does scanrel's existing constraints imply the partition constraint?
+ *
+ * Existing constraints includes its check constraints and column-level
+ * NOT NULL constraints and partConstraint describes the partition constraint.
+ */
+static bool
+PartConstraintImpliedByRelConstraint(Relation scanrel,
+ List *partConstraint)
+{
+ List *existConstraint = NIL;
+ TupleConstr *constr = RelationGetDescr(scanrel)->constr;
+ int num_check,
+ i;
+
+ if (constr && constr->has_not_null)
+ {
+ int natts = scanrel->rd_att->natts;
+
+ for (i = 1; i <= natts; i++)
+ {
+ Form_pg_attribute att = scanrel->rd_att->attrs[i - 1];
+
+ if (att->attnotnull && !att->attisdropped)
+ {
+ NullTest *ntest = makeNode(NullTest);
+
+ ntest->arg = (Expr *) makeVar(1,
+ i,
+ att->atttypid,
+ att->atttypmod,
+ att->attcollation,
+ 0);
+ ntest->nulltesttype = IS_NOT_NULL;
+
+ /*
+ * argisrow=false is correct even for a composite column,
+ * because attnotnull does not represent a SQL-spec IS NOT
+ * NULL test in such a case, just IS DISTINCT FROM NULL.
+ */
+ ntest->argisrow = false;
+ ntest->location = -1;
+ existConstraint = lappend(existConstraint, ntest);
+ }
+ }
+ }
+
+ num_check = (constr != NULL) ? constr->num_check : 0;
+ for (i = 0; i < num_check; i++)
+ {
+ Node *cexpr;
+
+ /*
+ * If this constraint hasn't been fully validated yet, we must ignore
+ * it here.
+ */
+ if (!constr->check[i].ccvalid)
+ continue;
+
+ cexpr = stringToNode(constr->check[i].ccbin);
+
+ /*
+ * Run each expression through const-simplification and
+ * canonicalization. It is necessary, because we will be comparing it
+ * to similarly-processed partition constraint expressions, and may
+ * fail to detect valid matches without this.
+ */
+ cexpr = eval_const_expressions(NULL, cexpr);
+ cexpr = (Node *) canonicalize_qual((Expr *) cexpr);
+
+ existConstraint = list_concat(existConstraint,
+ make_ands_implicit((Expr *) cexpr));
+ }
+
+ if (existConstraint != NIL)
+ existConstraint = list_make1(make_ands_explicit(existConstraint));
+
+ /* And away we go ... */
+ return predicate_implied_by(partConstraint, existConstraint, true);
+}
+
+/*
+ * ValidatePartitionConstraints
+ *
+ * Check whether all rows in the given table obey the given partition
+ * constraint; if so, it can be attached as a partition. We do this by
+ * scanning the table (or all of its leaf partitions) row by row, except when
+ * the existing constraints are sufficient to prove that the new partitioning
+ * constraint must already hold.
+ */
+static void
+ValidatePartitionConstraints(List **wqueue, Relation scanrel,
+ List *scanrel_children,
+ List *partConstraint)
+{
+ bool found_whole_row;
+ ListCell *lc;
+
+ if (partConstraint == NIL)
+ return;
+
+ /*
+ * Based on the table's existing constraints, determine if we can skip
+ * scanning the table to validate the partition constraint.
+ */
+ if (PartConstraintImpliedByRelConstraint(scanrel, partConstraint))
+ {
+ ereport(INFO,
+ (errmsg("partition constraint for table \"%s\" is implied by existing constraints",
+ RelationGetRelationName(scanrel))));
+ return;
+ }
+
+ /* Constraints proved insufficient, so we need to scan the table. */
+ foreach(lc, scanrel_children)
+ {
+ AlteredTableInfo *tab;
+ Oid part_relid = lfirst_oid(lc);
+ Relation part_rel;
+ List *my_partconstr = partConstraint;
+
+ /* Lock already taken */
+ if (part_relid != RelationGetRelid(scanrel))
+ part_rel = heap_open(part_relid, NoLock);
+ else
+ part_rel = scanrel;
+
+ /*
+ * Skip if the partition is itself a partitioned table. We can only
+ * ever scan RELKIND_RELATION relations.
+ */
+ if (part_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
+ {
+ if (part_rel != scanrel)
+ heap_close(part_rel, NoLock);
+ continue;
+ }
+
+ if (part_rel != scanrel)
+ {
+ /*
+ * Adjust the constraint for scanrel so that it matches this
+ * partition's attribute numbers.
+ */
+ my_partconstr = map_partition_varattnos(my_partconstr, 1,
+ part_rel, scanrel,
+ &found_whole_row);
+ /* There can never be a whole-row reference here */
+ if (found_whole_row)
+ elog(ERROR, "unexpected whole-row reference found in partition key");
+ }
+
+ /* Grab a work queue entry. */
+ tab = ATGetQueueEntry(wqueue, part_rel);
+ tab->partition_constraint = (Expr *) linitial(my_partconstr);
+
+ /* keep our lock until commit */
+ if (part_rel != scanrel)
+ heap_close(part_rel, NoLock);
+ }
+}
+
/*
* ALTER TABLE <name> ATTACH PARTITION <partition-name> FOR VALUES
*
Relation attachrel,
catalog;
List *attachrel_children;
- TupleConstr *attachrel_constr;
- List *partConstraint,
- *existConstraint;
+ List *partConstraint;
SysScanDesc scan;
ScanKeyData skey;
AttrNumber attno;
int natts;
TupleDesc tupleDesc;
- bool skip_validate = false;
ObjectAddress address;
const char *trigger_name;
bool found_whole_row;
if (found_whole_row)
elog(ERROR, "unexpected whole-row reference found in partition key");
- /*
- * Check if we can do away with having to scan the table being attached to
- * validate the partition constraint, by *proving* that the existing
- * constraints of the table *imply* the partition predicate. We include
- * the table's check constraints and NOT NULL constraints in the list of
- * clauses passed to predicate_implied_by().
- *
- * There is a case in which we cannot rely on just the result of the
- * proof.
- */
- attachrel_constr = tupleDesc->constr;
- existConstraint = NIL;
- if (attachrel_constr != NULL)
- {
- int num_check = attachrel_constr->num_check;
- int i;
-
- if (attachrel_constr->has_not_null)
- {
- int natts = attachrel->rd_att->natts;
-
- for (i = 1; i <= natts; i++)
- {
- Form_pg_attribute att = attachrel->rd_att->attrs[i - 1];
-
- if (att->attnotnull && !att->attisdropped)
- {
- NullTest *ntest = makeNode(NullTest);
-
- ntest->arg = (Expr *) makeVar(1,
- i,
- att->atttypid,
- att->atttypmod,
- att->attcollation,
- 0);
- ntest->nulltesttype = IS_NOT_NULL;
-
- /*
- * argisrow=false is correct even for a composite column,
- * because attnotnull does not represent a SQL-spec IS NOT
- * NULL test in such a case, just IS DISTINCT FROM NULL.
- */
- ntest->argisrow = false;
- ntest->location = -1;
- existConstraint = lappend(existConstraint, ntest);
- }
- }
- }
-
- for (i = 0; i < num_check; i++)
- {
- Node *cexpr;
-
- /*
- * If this constraint hasn't been fully validated yet, we must
- * ignore it here.
- */
- if (!attachrel_constr->check[i].ccvalid)
- continue;
-
- cexpr = stringToNode(attachrel_constr->check[i].ccbin);
-
- /*
- * Run each expression through const-simplification and
- * canonicalization. It is necessary, because we will be
- * comparing it to similarly-processed qual clauses, and may fail
- * to detect valid matches without this.
- */
- cexpr = eval_const_expressions(NULL, cexpr);
- cexpr = (Node *) canonicalize_qual((Expr *) cexpr);
-
- existConstraint = list_concat(existConstraint,
- make_ands_implicit((Expr *) cexpr));
- }
-
- existConstraint = list_make1(make_ands_explicit(existConstraint));
-
- /* And away we go ... */
- if (predicate_implied_by(partConstraint, existConstraint, true))
- skip_validate = true;
- }
-
- if (skip_validate)
- {
- /* No need to scan the table after all. */
- ereport(INFO,
- (errmsg("partition constraint for table \"%s\" is implied by existing constraints",
- RelationGetRelationName(attachrel))));
- }
- else
- {
- /* Constraints proved insufficient, so we need to scan the table. */
- ListCell *lc;
-
- foreach(lc, attachrel_children)
- {
- AlteredTableInfo *tab;
- Oid part_relid = lfirst_oid(lc);
- Relation part_rel;
- List *my_partconstr = partConstraint;
-
- /* Lock already taken */
- if (part_relid != RelationGetRelid(attachrel))
- part_rel = heap_open(part_relid, NoLock);
- else
- part_rel = attachrel;
-
- /*
- * Skip if the partition is itself a partitioned table. We can
- * only ever scan RELKIND_RELATION relations.
- */
- if (part_rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE)
- {
- if (part_rel != attachrel)
- heap_close(part_rel, NoLock);
- continue;
- }
-
- if (part_rel != attachrel)
- {
- /*
- * Adjust the constraint that we constructed above for
- * attachRel so that it matches this partition's attribute
- * numbers.
- */
- my_partconstr = map_partition_varattnos(my_partconstr, 1,
- part_rel, attachrel,
- &found_whole_row);
- /* There can never be a whole-row reference here */
- if (found_whole_row)
- elog(ERROR, "unexpected whole-row reference found in partition key");
- }
-
- /* Grab a work queue entry. */
- tab = ATGetQueueEntry(wqueue, part_rel);
- tab->partition_constraint = (Expr *) linitial(my_partconstr);
-
- /* keep our lock until commit */
- if (part_rel != attachrel)
- heap_close(part_rel, NoLock);
- }
- }
+ /* Validate partition constraints against the table being attached. */
+ ValidatePartitionConstraints(wqueue, attachrel, attachrel_children,
+ partConstraint);
ObjectAddressSet(address, RelationRelationId, RelationGetRelid(attachrel));
projects / postgresql / commitdiff