130 lines
3.9 KiB
Go
130 lines
3.9 KiB
Go
// Copyright 2024 Dolthub, Inc.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package node
|
|
|
|
import (
|
|
"context"
|
|
|
|
"github.com/cockroachdb/errors"
|
|
"github.com/dolthub/go-mysql-server/sql"
|
|
"github.com/dolthub/go-mysql-server/sql/plan"
|
|
vitess "github.com/dolthub/vitess/go/vt/sqlparser"
|
|
|
|
"github.com/dolthub/doltgresql/core"
|
|
"github.com/dolthub/doltgresql/core/id"
|
|
)
|
|
|
|
// DropSequence handles the DROP SEQUENCE statement.
|
|
type DropSequence struct {
|
|
schema string
|
|
sequence string
|
|
ifExists bool
|
|
cascade bool
|
|
}
|
|
|
|
var _ sql.ExecSourceRel = (*DropSequence)(nil)
|
|
var _ vitess.Injectable = (*DropSequence)(nil)
|
|
|
|
// NewDropSequence returns a new *DropSequence.
|
|
func NewDropSequence(ifExists bool, schema string, sequence string, cascade bool) *DropSequence {
|
|
return &DropSequence{
|
|
schema: schema,
|
|
sequence: sequence,
|
|
ifExists: ifExists,
|
|
cascade: cascade,
|
|
}
|
|
}
|
|
|
|
// Children implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) Children() []sql.Node {
|
|
return nil
|
|
}
|
|
|
|
// IsReadOnly implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) IsReadOnly() bool {
|
|
return false
|
|
}
|
|
|
|
// Resolved implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) Resolved() bool {
|
|
return true
|
|
}
|
|
|
|
// RowIter implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) RowIter(ctx *sql.Context, r sql.Row) (sql.RowIter, error) {
|
|
schema, err := core.GetSchemaName(ctx, nil, c.schema)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
relationType, err := core.GetRelationType(ctx, schema, c.sequence)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if relationType == core.RelationType_DoesNotExist {
|
|
if c.ifExists {
|
|
// TODO: issue a notice
|
|
return sql.RowsToRowIter(), nil
|
|
}
|
|
return nil, errors.Errorf(`sequence "%s" does not exist`, c.sequence)
|
|
}
|
|
// TODO: we always use the current database for this operation, but it should also be possible drop a sequence in
|
|
// a different DB (e.g. on a different branch)
|
|
collection, err := core.GetSequencesCollectionFromContext(ctx, ctx.GetCurrentDatabase())
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
sequenceID := id.NewSequence(schema, c.sequence)
|
|
sequence, err := collection.GetSequence(ctx, sequenceID)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
if sequence.OwnerTable.IsValid() {
|
|
if c.cascade {
|
|
// TODO: if the sequence is referenced by the column's default value, then we also need to delete the default
|
|
return nil, errors.Errorf(`cascading sequence drops are not yet supported`)
|
|
} else {
|
|
// TODO: this error is only true if the sequence is referenced by the column's default value
|
|
return nil, errors.Errorf(`cannot drop sequence %s because other objects depend on it`, c.sequence)
|
|
}
|
|
}
|
|
if err = collection.DropSequence(ctx, sequenceID); err != nil {
|
|
return nil, err
|
|
}
|
|
return sql.RowsToRowIter(), nil
|
|
}
|
|
|
|
// Schema implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) Schema(ctx *sql.Context) sql.Schema {
|
|
return nil
|
|
}
|
|
|
|
// String implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) String() string {
|
|
return "DROP SEQUENCE"
|
|
}
|
|
|
|
// WithChildren implements the interface sql.ExecSourceRel.
|
|
func (c *DropSequence) WithChildren(ctx *sql.Context, children ...sql.Node) (sql.Node, error) {
|
|
return plan.NillaryWithChildren(c, children...)
|
|
}
|
|
|
|
// WithResolvedChildren implements the interface vitess.Injectable.
|
|
func (c *DropSequence) WithResolvedChildren(ctx context.Context, children []any) (any, error) {
|
|
if len(children) != 0 {
|
|
return nil, ErrVitessChildCount.New(0, len(children))
|
|
}
|
|
return c, nil
|
|
}
|