chore: import upstream snapshot with attribution

server/node/alter_sequence.go

@@ -0,0 +1,171 @@
+// Copyright 2025 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/dolt/go/libraries/doltcore/doltdb"
+	"github.com/dolthub/dolt/go/libraries/doltcore/sqle/dsess"
+	"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/jackc/pgx/v5/pgproto3"
+
+	"github.com/dolthub/doltgresql/core"
+	"github.com/dolthub/doltgresql/core/id"
+)
+
+// AlterSequence handles the ALTER SEQUENCE statement.
+type AlterSequence struct {
+	ifExists       bool
+	targetSchema   string
+	targetSequence string
+	ownedBy        AlterSequenceOwnedBy
+	warnings       []string
+}
+
+// AlterSequenceOwnedBy is an option in AlterSequence to represent OWNED BY.
+type AlterSequenceOwnedBy struct {
+	IsSet  bool
+	Table  string
+	Column string
+}
+
+var _ sql.ExecSourceRel = (*AlterSequence)(nil)
+var _ vitess.Injectable = (*AlterSequence)(nil)
+
+// NewAlterSequence returns a new *AlterSequence.
+func NewAlterSequence(ifExists bool, targetSchema string, targetSequence string, ownedBy AlterSequenceOwnedBy, warnings ...string) *AlterSequence {
+	return &AlterSequence{
+		ifExists:       ifExists,
+		targetSchema:   targetSchema,
+		targetSequence: targetSequence,
+		ownedBy:        ownedBy,
+		warnings:       warnings,
+	}
+}
+
+// Children implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) Children() []sql.Node {
+	return nil
+}
+
+// IsReadOnly implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) IsReadOnly() bool {
+	return false
+}
+
+// Resolved implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) Resolved() bool {
+	return true
+}
+
+// RowIter implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) RowIter(ctx *sql.Context, r sql.Row) (sql.RowIter, error) {
+	targetSchema, err := core.GetSchemaName(ctx, nil, c.targetSchema)
+	if err != nil {
+		return nil, err
+	}
+	target := id.NewSequence(targetSchema, c.targetSequence)
+	collection, err := core.GetSequencesCollectionFromContext(ctx, ctx.GetCurrentDatabase())
+	if err != nil {
+		return nil, err
+	}
+	if !collection.HasSequence(ctx, target) {
+		if c.ifExists {
+			return sql.RowsToRowIter(), nil
+		}
+		return nil, errors.Errorf(`relation "%s" does not exist`, c.targetSequence)
+	}
+	seq, err := collection.GetSequence(ctx, target)
+	if err != nil {
+		return nil, err
+	}
+
+	if c.ownedBy.IsSet {
+		if len(c.ownedBy.Table) > 0 {
+			relationType, err := core.GetRelationType(ctx, targetSchema, c.ownedBy.Table)
+			if err != nil {
+				return nil, err
+			}
+			if relationType == core.RelationType_DoesNotExist {
+				return nil, errors.Errorf(`relation "%s" does not exist`, c.ownedBy.Table)
+			} else if relationType != core.RelationType_Table {
+				return nil, errors.Errorf(`sequence cannot be owned by relation "%s"`, c.ownedBy.Table)
+			}
+
+			table, err := core.GetSqlTableFromContext(ctx, "", doltdb.TableName{Name: c.ownedBy.Table, Schema: targetSchema})
+			if err != nil {
+				return nil, err
+			}
+			if table == nil {
+				return nil, errors.Errorf(`table "%s" cannot be found but says it exists`, c.ownedBy.Table)
+			}
+			var tableColumn *sql.Column
+			for _, col := range table.Schema(ctx) {
+				if col.Name == c.ownedBy.Column {
+					tableColumn = col.Copy()
+					break
+				}
+			}
+			if tableColumn == nil {
+				return nil, errors.Errorf(`column "%s" of relation "%s" does not exist`,
+					c.ownedBy.Column, c.ownedBy.Table)
+			}
+			// We've verified the existence of the table's column, so we can assign it now
+			seq.OwnerTable = id.NewTable(targetSchema, c.ownedBy.Table)
+			seq.OwnerColumn = c.ownedBy.Column
+		} else {
+			seq.OwnerTable = ""
+			seq.OwnerColumn = ""
+		}
+	}
+	// Display any warnings that were encountered during parsing
+	for _, warning := range c.warnings {
+		noticeResponse := &pgproto3.NoticeResponse{
+			Severity: "WARNING",
+			Message:  warning,
+		}
+		sess := dsess.DSessFromSess(ctx.Session)
+		sess.Notice(noticeResponse)
+	}
+	// Any changes made to the sequence will be persisted at the end of the transaction, so we can just return now
+	return sql.RowsToRowIter(), nil
+}
+
+// Schema implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) Schema(ctx *sql.Context) sql.Schema {
+	return nil
+}
+
+// String implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) String() string {
+	return "ALTER SEQUENCE"
+}
+
+// WithChildren implements the interface sql.ExecSourceRel.
+func (c *AlterSequence) WithChildren(ctx *sql.Context, children ...sql.Node) (sql.Node, error) {
+	return plan.NillaryWithChildren(c, children...)
+}
+
+// WithResolvedChildren implements the interface vitess.Injectable.
+func (c *AlterSequence) WithResolvedChildren(ctx context.Context, children []any) (any, error) {
+	if len(children) != 0 {
+		return nil, ErrVitessChildCount.New(0, len(children))
+	}
+	return c, nil
+}