Make sure to rewrite last_insert_id() for DELETEs

Signed-off-by: Andres Taylor <andres@planetscale.com>

go/vt/vtgate/planbuilder/builder.go

@@ -278,7 +278,7 @@ func BuildFromStmt(query string, stmt sqlparser.Statement, vschema ContextVSchem
  case *sqlparser.Update:
  instruction, needsLastInsertID, needsDBName, err = buildUpdatePlan(stmt, vschema)
  case *sqlparser.Delete:
- instruction, err = buildDeletePlan(stmt, vschema)
+ instruction, needsLastInsertID, needsDBName, err = buildDeletePlan(stmt, vschema)
  case *sqlparser.Union:
  instruction, needsLastInsertID, needsDBName, err = buildUnionPlan(stmt, vschema)
  case *sqlparser.Set:

go/vt/vtgate/planbuilder/delete.go

@@ -29,31 +29,31 @@ import (
 )
 
 // buildDeletePlan builds the instructions for a DELETE statement.
-func buildDeletePlan(del *sqlparser.Delete, vschema ContextVSchema) (*engine.Delete, error) {
+func buildDeletePlan(del *sqlparser.Delete, vschema ContextVSchema) (_ *engine.Delete, needsLastInsertID bool, needDbName bool, _ error) {
  edel := &engine.Delete{}
  pb := newPrimitiveBuilder(vschema, newJointab(sqlparser.GetBindvars(del)))
  ro, err := pb.processDMLTable(del.TableExprs)
  if err != nil {
- return nil, err
+ return nil, false, false, err
  }
  edel.Query = generateQuery(del)
  edel.Keyspace = ro.eroute.Keyspace
  if !edel.Keyspace.Sharded {
  // We only validate non-table subexpressions because the previous analysis has already validated them.
  if !pb.finalizeUnshardedDMLSubqueries(del.Targets, del.Where, del.OrderBy, del.Limit) {
- return nil, errors.New("unsupported: sharded subqueries in DML")
+ return nil, false, false, errors.New("unsupported: sharded subqueries in DML")
  }
  edel.Opcode = engine.DeleteUnsharded
  // Generate query after all the analysis. Otherwise table name substitutions for
  // routed tables won't happen.
  edel.Query = generateQuery(del)
- return edel, nil
+ return edel, pb.needsLastInsertID, pb.needsDbName, nil
  }
  if del.Targets != nil || ro.vschemaTable == nil {
- return nil, errors.New("unsupported: multi-table delete statement in sharded keyspace")
+ return nil, false, false, errors.New("unsupported: multi-table delete statement in sharded keyspace")
  }
  if hasSubquery(del) {
- return nil, errors.New("unsupported: subqueries in sharded DML")
+ return nil, false, false, errors.New("unsupported: subqueries in sharded DML")
  }
  edel.Table = ro.vschemaTable
  // Generate query after all the analysis. Otherwise table name substitutions for
@@ -68,11 +68,11 @@ func buildDeletePlan(del *sqlparser.Delete, vschema ContextVSchema) (*engine.Del
  edel.QueryTimeout = queryTimeout(directives)
  if ro.eroute.TargetDestination != nil {
  if ro.eroute.TargetTabletType != topodatapb.TabletType_MASTER {
- return nil, vterrors.Errorf(vtrpcpb.Code_INVALID_ARGUMENT, "unsupported: DELETE statement with a replica target")
+ return nil, false, false, vterrors.Errorf(vtrpcpb.Code_INVALID_ARGUMENT, "unsupported: DELETE statement with a replica target")
  }
  edel.Opcode = engine.DeleteByDestination
  edel.TargetDestination = ro.eroute.TargetDestination
- return edel, nil
+ return edel, pb.needsLastInsertID, pb.needsDbName, nil
  }
  edel.Vindex, edel.Values, err = getDMLRouting(del.Where, edel.Table)
  // We couldn't generate a route for a single shard
@@ -85,15 +85,15 @@ func buildDeletePlan(del *sqlparser.Delete, vschema ContextVSchema) (*engine.Del
 
  if edel.Opcode == engine.DeleteScatter {
  if len(edel.Table.Owned) != 0 {
- return edel, errors.New("unsupported: multi shard delete on a table with owned lookup vindexes")
+ return nil, false, false, errors.New("unsupported: multi shard delete on a table with owned lookup vindexes")
  }
  if del.Limit != nil {
- return edel, errors.New("unsupported: multi shard delete with limit")
+ return nil, false, false, errors.New("unsupported: multi shard delete with limit")
  }
  }
 
  edel.OwnedVindexQuery = generateDeleteSubquery(del, edel.Table)
- return edel, nil
+ return edel, pb.needsLastInsertID, pb.needsDbName, nil
 }
 
 // generateDeleteSubquery generates the query to fetch the rows

go/vt/vtgate/planbuilder/expression_rewriting.go

@@ -47,8 +47,8 @@ func RewriteAndUpdateBuilder(in sqlparser.Expr, pb *primitiveBuilder) (sqlparser
 }
 
 // Rewrite will rewrite an expression. Currently it does the following rewrites:
-// - `last_insert_id()` => `:vtlastid`
-// - `database()` => `:vtdbname`
+// - `last_insert_id()` => `:__lastInsertId`
+// - `database()` => `:__vtdbname`
 func Rewrite(in sqlparser.Expr) (*RewriteResult, error) {
  rewrites := make(map[*sqlparser.FuncExpr]sqlparser.Expr)
  liid := false