Add support for multi table deletes with foreign keys

go/test/endtoend/vtgate/foreignkey/fk_fuzz_test.go

@@ -181,15 +181,34 @@ func (fz *fuzzer) generateUpdateDMLQuery() string {
 	}
 }
 
-// generateDeleteDMLQuery generates a DELETE query from the parameters for the fuzzer.
-func (fz *fuzzer) generateDeleteDMLQuery() string {
+// generateDeleteDMLQuery generates a DELETE query using 1 table from the parameters for the fuzzer.
+func (fz *fuzzer) generateSingleDeleteDMLQuery() string {
 	tableId := rand.Intn(len(fkTables))
 	idValue := 1 + rand.Intn(fz.maxValForId)
 	setVarFkChecksVal := fz.getSetVarFkChecksVal()
 	query := fmt.Sprintf("delete %vfrom %v where id = %v", setVarFkChecksVal, fkTables[tableId], idValue)
 	return query
 }
 
+// generateMultiDeleteDMLQuery generates a DELETE query using 2 tables from the parameters for the fuzzer.
+func (fz *fuzzer) generateMultiDeleteDMLQuery() string {
+	tableId := rand.Intn(len(fkTables))
+	tableId2 := rand.Intn(len(fkTables))
+	idValue := 1 + rand.Intn(fz.maxValForId)
+	setVarFkChecksVal := fz.getSetVarFkChecksVal()
+	query := fmt.Sprintf("delete %v%v from %v join %v using (id) where %v.id = %v", setVarFkChecksVal, fkTables[tableId], fkTables[tableId], fkTables[tableId2], fkTables[tableId], idValue)
+	return query
+}
+
+// generateDeleteDMLQuery generates a DELETE query from the parameters for the fuzzer.
+func (fz *fuzzer) generateDeleteDMLQuery() string {
+	multiTableDelete := rand.Intn(2) + 1
+	if multiTableDelete == 1 {
+		return fz.generateSingleDeleteDMLQuery()
+	}
+	return fz.generateMultiDeleteDMLQuery()
+}
+
 // start starts running the fuzzer.
 func (fz *fuzzer) start(t *testing.T, sharded bool) {
 	// We mark the fuzzer thread to be running now.

go/test/endtoend/vtgate/foreignkey/fk_test.go

@@ -672,6 +672,21 @@ func TestFkScenarios(t *testing.T) {
 			assertionQueries: []string{
 				"select * from fk_t20 order by id",
 			},
+		}, {
+			name: "Multi Table Delete success",
+			dataQueries: []string{
+				"insert into fk_t15(id, col) values (1, 7), (2, 9)",
+				"insert into fk_t16(id, col) values (1, 7), (2, 9)",
+				"insert into fk_t17(id, col) values (1, 7)",
+				"insert into fk_t19(id, col) values (1, 7)",
+			},
+			dmlQuery: "delete fk_t15 from fk_t15 join fk_t17 using id",
+			assertionQueries: []string{
+				"select * from fk_t15 order by id",
+				"select * from fk_t16 order by id",
+				"select * from fk_t17 order by id",
+				"select * from fk_t19 order by id",
+			},
 		},
 	}
 

go/vt/sqlparser/ast.go

@@ -352,7 +352,7 @@ type (
 		With       *With
 		Comments   *ParsedComments
 		Ignore     Ignore
-		TableExprs TableExprs
+		TableExprs []TableExpr
 		Exprs      UpdateExprs
 		Where      *Where
 		OrderBy    OrderBy
@@ -365,7 +365,7 @@ type (
 		With       *With
 		Ignore     Ignore
 		Comments   *ParsedComments
-		TableExprs TableExprs
+		TableExprs []TableExpr
 		Targets    TableNames
 		Partitions Partitions
 		Where      *Where

go/vt/sqlparser/ast_format.go

@@ -158,9 +158,14 @@
 	if node.With != nil {
 		buf.astPrintf(node, "%v", node.With)
 	}
-	buf.astPrintf(node, "update %v%s%v set %v%v%v%v",
-		node.Comments, node.Ignore.ToString(), node.TableExprs,
-		node.Exprs, node.Where, node.OrderBy, node.Limit)
+	buf.astPrintf(node, "update %v%s",
+		node.Comments, node.Ignore.ToString())
+	prefix := ""
+	for _, expr := range node.TableExprs {
+		buf.astPrintf(node, "%s%v", prefix, expr)
+		prefix = ", "
+	}
+	buf.astPrintf(node, " set %v%v%v%v", node.Exprs, node.Where, node.OrderBy, node.Limit)
 }
 
 // Format formats the node.
@@ -175,7 +180,12 @@
 	if node.Targets != nil && !node.isSingleAliasExpr() {
 		buf.astPrintf(node, "%v ", node.Targets)
 	}
-	buf.astPrintf(node, "from %v%v%v%v%v", node.TableExprs, node.Partitions, node.Where, node.OrderBy, node.Limit)
+	prefix := "from "
+	for _, expr := range node.TableExprs {
+		buf.astPrintf(node, "%s%v", prefix, expr)
+		prefix = ", "
+	}
+	buf.astPrintf(node, "%v%v%v%v", node.Partitions, node.Where, node.OrderBy, node.Limit)
 }
 
 // Format formats the node.

go/vt/sqlparser/ast_funcs.go

@@ -2151,7 +2151,7 @@
 }
 
 // RemoveKeyspaceInCol removes the Qualifier.Qualifier on all ColNames in the AST
 func RemoveKeyspaceInCol(in SQLNode) {
 	// Walk will only return an error if we return an error from the inner func. safe to ignore here
 	_ = Walk(func(node SQLNode) (kontinue bool, err error) {
 		if col, ok := node.(*ColName); ok && col.Qualifier.Qualifier.NotEmpty() {
@@ -2176,20 +2176,20 @@
 }
 
 // RemoveKeyspace removes the Qualifier.Qualifier on all ColNames and Qualifier on all TableNames in the AST
 func RemoveKeyspace(in SQLNode) {
 	Rewrite(in, nil, func(cursor *Cursor) bool {
 		switch expr := cursor.Node().(type) {
 		case *ColName:
 			if expr.Qualifier.Qualifier.NotEmpty() {
 				expr.Qualifier.Qualifier = NewIdentifierCS("")
 			}
 		case TableName:
 			if expr.Qualifier.NotEmpty() {
 				expr.Qualifier = NewIdentifierCS("")
 				cursor.Replace(expr)
 			}
 		}
 		return true
 	})
 }
 
@@ -2566,7 +2566,7 @@
 	return isAliasExpr
 }
 
-func (node TableExprs) MultiTable() bool {
+func MultiTable(node []TableExpr) bool {
 	if len(node) > 1 {
 		return true
 	}