Add DDL for dropping sequence and auto_increment

Signed-off-by: David Piegza <[email protected]>

go/vt/sqlparser/ast_format.go

@@ -259,8 +259,12 @@ func (node *AlterVschema) Format(buf *TrackedBuffer) {
 		buf.astPrintf(node, "alter vschema on %v drop vindex %v", node.Table, node.VindexSpec.Name)
 	case AddSequenceDDLAction:
 		buf.astPrintf(node, "alter vschema add sequence %v", node.Table)
+	case DropSequenceDDLAction:
+		buf.astPrintf(node, "alter vschema drop sequence %v", node.Table)
 	case AddAutoIncDDLAction:
 		buf.astPrintf(node, "alter vschema on %v add auto_increment %v", node.Table, node.AutoIncSpec)
+	case DropAutoIncDDLAction:
+		buf.astPrintf(node, "alter vschema on %v drop auto_increment %v", node.Table, node.AutoIncSpec)
 	default:
 		buf.astPrintf(node, "%s table %v", node.Action.ToString(), node.Table)
 	}

go/vt/sqlparser/ast_funcs.go

@@ -1129,8 +1129,12 @@ func (action DDLAction) ToString() string {
 		return DropColVindexStr
 	case AddSequenceDDLAction:
 		return AddSequenceStr
+	case DropSequenceDDLAction:
+		return DropSequenceStr
 	case AddAutoIncDDLAction:
 		return AddAutoIncStr
+	case DropAutoIncDDLAction:
+		return DropAutoIncStr
 	default:
 		return "Unknown DDL Action"
 	}

go/vt/sqlparser/constants.go

@@ -68,7 +68,9 @@ const (
 	AddColVindexStr     = "on table add vindex"
 	DropColVindexStr    = "on table drop vindex"
 	AddSequenceStr      = "add sequence"
+	DropSequenceStr     = "drop sequence"
 	AddAutoIncStr       = "add auto_increment"
+	DropAutoIncStr      = "drop auto_increment"
 
 	// Partition and subpartition type strings
 	HashTypeStr  = "hash"
@@ -452,7 +454,9 @@ const (
 	AddColVindexDDLAction
 	DropColVindexDDLAction
 	AddSequenceDDLAction
+	DropSequenceDDLAction
 	AddAutoIncDDLAction
+	DropAutoIncDDLAction
 	RevertDDLAction
 )