feat(spanner/spansql): add ROW DELETION POLICY parsing

spanner/spansql/parser.go

@@ -933,13 +933,15 @@ func (p *parser) eat(want ...string) bool {
 	return true
 }
 
-func (p *parser) expect(want string) *parseError {
-	tok := p.next()
-	if tok.err != nil {
-		return tok.err
-	}
-	if !tok.caseEqual(want) {
-		return p.errorf("got %q while expecting %q", tok.value, want)
+func (p *parser) expect(want ...string) *parseError {
+	for _, w := range want {
+		tok := p.next()
+		if tok.err != nil {
+			return tok.err
+		}
+		if !tok.caseEqual(w) {
+			return p.errorf("got %q while expecting %q", tok.value, w)
+		}
 	}
 	return nil
 }
@@ -1082,6 +1084,13 @@ func (p *parser) parseCreateTable() (*CreateTable, *parseError) {
 			ct.Interleave.OnDelete = od
 		}
 	}
+	if p.eat(",", "ROW", "DELETION", "POLICY") {
+		rdp, err := p.parseRowDeletionPolicy()
+		if err != nil {
+			return nil, err
+		}
+		ct.RowDeletionPolicy = &rdp
+	}
 
 	return ct, nil
 }
@@ -1236,6 +1245,15 @@ func (p *parser) parseAlterTable() (*AlterTable, *parseError) {
 			return a, nil
 		}
 
+		if p.eat("ROW", "DELETION", "POLICY") {
+			rdp, err := p.parseRowDeletionPolicy()
+			if err != nil {
+				return nil, err
+			}
+			a.Alteration = AddRowDeletionPolicy{RowDeletionPolicy: rdp}
+			return a, nil
+		}
+
 		// TODO: "COLUMN" is optional.
 		if err := p.expect("COLUMN"); err != nil {
 			return nil, err
@@ -1256,6 +1274,11 @@ func (p *parser) parseAlterTable() (*AlterTable, *parseError) {
 			return a, nil
 		}
 
+		if p.eat("ROW", "DELETION", "POLICY") {
+			a.Alteration = DropRowDeletionPolicy{}
+			return a, nil
+		}
+
 		// TODO: "COLUMN" is optional.
 		if err := p.expect("COLUMN"); err != nil {
 			return nil, err
@@ -1297,7 +1320,17 @@ func (p *parser) parseAlterTable() (*AlterTable, *parseError) {
 			Alteration: ca,
 		}
 		return a, nil
+	case tok.caseEqual("REPLACE"):
+		if p.eat("ROW", "DELETION", "POLICY") {
+			rdp, err := p.parseRowDeletionPolicy()
+			if err != nil {
+				return nil, err
+			}
+			a.Alteration = ReplaceRowDeletionPolicy{RowDeletionPolicy: rdp}
+			return a, nil
+		}
 	}
+	return a, nil
 }
 
 func (p *parser) parseAlterDatabase() (*AlterDatabase, *parseError) {
@@ -2963,6 +2996,37 @@ func (p *parser) parseOnDelete() (OnDelete, *parseError) {
 	return NoActionOnDelete, nil
 }
 
+func (p *parser) parseRowDeletionPolicy() (RowDeletionPolicy, *parseError) {
+	if err := p.expect("(", "OLDER_THAN", "("); err != nil {
+		return RowDeletionPolicy{}, err
+	}
+	cname, err := p.parseTableOrIndexOrColumnName()
+	if err != nil {
+		return RowDeletionPolicy{}, err
+	}
+	if err := p.expect(",", "INTERVAL"); err != nil {
+		return RowDeletionPolicy{}, err
+	}
+	tok := p.next()
+	if tok.err != nil {
+		return RowDeletionPolicy{}, tok.err
+	}
+	if tok.typ != int64Token {
+		return RowDeletionPolicy{}, p.errorf("got %q, expected int64 token", tok.value)
+	}
+	n, serr := strconv.ParseInt(tok.value, tok.int64Base, 64)
+	if serr != nil {
+		return RowDeletionPolicy{}, p.errorf("%v", serr)
+	}
+	if err := p.expect("DAY", ")", ")"); err != nil {
+		return RowDeletionPolicy{}, err
+	}
+	return RowDeletionPolicy{
+		Column:  cname,
+		NumDays: n,
+	}, nil
+}
+
 // parseCommaList parses a comma-separated list enclosed by bra and ket,
 // delegating to f for the individual element parsing.
 // Only invoke this with symbols as bra/ket; they are matched literally, not case insensitively.

spanner/spansql/parser_test.go

@@ -477,6 +477,17 @@ func TestParseDDL(t *testing.T) {
 			NameLen INT64 AS (char_length(Name)) STORED,
 		) PRIMARY KEY (Name);
 
+		-- Table with row deletion policy.
+		CREATE TABLE WithRowDeletionPolicy (
+			Name STRING(MAX) NOT NULL,
+			DelTimestamp TIMESTAMP NOT NULL,
+		) PRIMARY KEY (Name)
+		, ROW DELETION POLICY ( OLDER_THAN ( DelTimestamp, INTERVAL 30 DAY ));
+
+		ALTER TABLE WithRowDeletionPolicy DROP ROW DELETION POLICY;
+		ALTER TABLE WithRowDeletionPolicy ADD ROW DELETION POLICY ( OLDER_THAN ( DelTimestamp, INTERVAL 30 DAY ));
+		ALTER TABLE WithRowDeletionPolicy REPLACE ROW DELETION POLICY ( OLDER_THAN ( DelTimestamp, INTERVAL 30 DAY ));
+
 		-- Trailing comment at end of file.
 		`, &DDL{Filename: "filename", List: []DDLStmt{
 			&CreateTable{
@@ -628,6 +639,44 @@ func TestParseDDL(t *testing.T) {
 				PrimaryKey: []KeyPart{{Column: "Name"}},
 				Position:   line(44),
 			},
+			&CreateTable{
+				Name: "WithRowDeletionPolicy",
+				Columns: []ColumnDef{
+					{Name: "Name", Type: Type{Base: String, Len: MaxLen}, NotNull: true, Position: line(51)},
+					{Name: "DelTimestamp", Type: Type{Base: Timestamp}, NotNull: true, Position: line(52)},
+				},
+				PrimaryKey: []KeyPart{{Column: "Name"}},
+				RowDeletionPolicy: &RowDeletionPolicy{
+					Column:  ID("DelTimestamp"),
+					NumDays: 30,
+				},
+				Position: line(50),
+			},
+			&AlterTable{
+				Name:       "WithRowDeletionPolicy",
+				Alteration: DropRowDeletionPolicy{},
+				Position:   line(56),
+			},
+			&AlterTable{
+				Name: "WithRowDeletionPolicy",
+				Alteration: AddRowDeletionPolicy{
+					RowDeletionPolicy: RowDeletionPolicy{
+						Column:  ID("DelTimestamp"),
+						NumDays: 30,
+					},
+				},
+				Position: line(57),
+			},
+			&AlterTable{
+				Name: "WithRowDeletionPolicy",
+				Alteration: ReplaceRowDeletionPolicy{
+					RowDeletionPolicy: RowDeletionPolicy{
+						Column:  ID("DelTimestamp"),
+						NumDays: 30,
+					},
+				},
+				Position: line(58),
+			},
 		}, Comments: []*Comment{
 			{Marker: "#", Start: line(2), End: line(2),
 				Text: []string{"This is a comment."}},
@@ -647,9 +696,10 @@ func TestParseDDL(t *testing.T) {
 			{Marker: "--", Isolated: true, Start: line(38), End: line(38), Text: []string{"leading multi comment immediately after inline comment"}},
 
 			{Marker: "--", Isolated: true, Start: line(43), End: line(43), Text: []string{"Table with generated column."}},
+			{Marker: "--", Isolated: true, Start: line(49), End: line(49), Text: []string{"Table with row deletion policy."}},
 
 			// Comment after everything else.
-			{Marker: "--", Isolated: true, Start: line(49), End: line(49), Text: []string{"Trailing comment at end of file."}},
+			{Marker: "--", Isolated: true, Start: line(60), End: line(60), Text: []string{"Trailing comment at end of file."}},
 		}}},
 		// No trailing comma:
 		{`ALTER TABLE T ADD COLUMN C2 INT64`, &DDL{Filename: "filename", List: []DDLStmt{

spanner/spansql/sql.go

@@ -56,6 +56,9 @@ func (ct CreateTable) SQL() string {
 	if il := ct.Interleave; il != nil {
 		str += ",\n  INTERLEAVE IN PARENT " + il.Parent.SQL() + " ON DELETE " + il.OnDelete.SQL()
 	}
+	if rdp := ct.RowDeletionPolicy; rdp != nil {
+		str += ",\n  " + rdp.SQL()
+	}
 	return str
 }
 
@@ -130,6 +133,17 @@ func (ac AlterColumn) SQL() string {
 	return "ALTER COLUMN " + ac.Name.SQL() + " " + ac.Alteration.SQL()
 }
 
+func (ardp AddRowDeletionPolicy) SQL() string {
+	return "ADD " + ardp.RowDeletionPolicy.SQL()
+}
+
+func (rrdp ReplaceRowDeletionPolicy) SQL() string {
+	return "REPLACE " + rrdp.RowDeletionPolicy.SQL()
+}
+
+func (drdp DropRowDeletionPolicy) SQL() string {
+	return "DROP ROW DELETION POLICY"
+}
 func (sct SetColumnType) SQL() string {
 	str := sct.Type.SQL()
 	if sct.NotNull {
@@ -246,6 +260,10 @@ func (tc TableConstraint) SQL() string {
 	return str
 }
 
+func (rdp RowDeletionPolicy) SQL() string {
+	return "ROW DELETION POLICY ( OLDER_THAN ( " + rdp.Column.SQL() + ", INTERVAL " + strconv.FormatInt(rdp.NumDays, 10) + " DAY ))"
+}
+
 func (fk ForeignKey) SQL() string {
 	str := "FOREIGN KEY (" + idList(fk.Columns, ", ")
 	str += ") REFERENCES " + fk.RefTable.SQL() + " ("

spanner/spansql/sql_test.go

@@ -135,6 +135,27 @@ func TestSQL(t *testing.T) {
   INTERLEAVE IN PARENT Ta ON DELETE CASCADE`,
 			reparseDDL,
 		},
+		{
+			&CreateTable{
+				Name: "WithRowDeletionPolicy",
+				Columns: []ColumnDef{
+					{Name: "Name", Type: Type{Base: String, Len: MaxLen}, NotNull: true, Position: line(2)},
+					{Name: "DelTimestamp", Type: Type{Base: Timestamp}, NotNull: true, Position: line(3)},
+				},
+				PrimaryKey: []KeyPart{{Column: "Name"}},
+				RowDeletionPolicy: &RowDeletionPolicy{
+					Column:  ID("DelTimestamp"),
+					NumDays: 30,
+				},
+				Position: line(1),
+			},
+			`CREATE TABLE WithRowDeletionPolicy (
+  Name STRING(MAX) NOT NULL,
+  DelTimestamp TIMESTAMP NOT NULL,
+) PRIMARY KEY(Name),
+  ROW DELETION POLICY ( OLDER_THAN ( DelTimestamp, INTERVAL 30 DAY ))`,
+			reparseDDL,
+		},
 		{
 			&DropTable{
 				Name:     "Ta",
@@ -230,6 +251,43 @@ func TestSQL(t *testing.T) {
 			"ALTER TABLE Ta ALTER COLUMN Ci SET OPTIONS (allow_commit_timestamp = null)",
 			reparseDDL,
 		},
+		{
+			&AlterTable{
+				Name:       "WithRowDeletionPolicy",
+				Alteration: DropRowDeletionPolicy{},
+				Position:   line(1),
+			},
+			"ALTER TABLE WithRowDeletionPolicy DROP ROW DELETION POLICY",
+			reparseDDL,
+		},
+		{
+			&AlterTable{
+				Name: "WithRowDeletionPolicy",
+				Alteration: AddRowDeletionPolicy{
+					RowDeletionPolicy: RowDeletionPolicy{
+						Column:  ID("DelTimestamp"),
+						NumDays: 30,
+					},
+				},
+				Position: line(1),
+			},
+			"ALTER TABLE WithRowDeletionPolicy ADD ROW DELETION POLICY ( OLDER_THAN ( DelTimestamp, INTERVAL 30 DAY ))",
+			reparseDDL,
+		},
+		{
+			&AlterTable{
+				Name: "WithRowDeletionPolicy",
+				Alteration: ReplaceRowDeletionPolicy{
+					RowDeletionPolicy: RowDeletionPolicy{
+						Column:  ID("DelTimestamp"),
+						NumDays: 30,
+					},
+				},
+				Position: line(1),
+			},
+			"ALTER TABLE WithRowDeletionPolicy REPLACE ROW DELETION POLICY ( OLDER_THAN ( DelTimestamp, INTERVAL 30 DAY ))",
+			reparseDDL,
+		},
 		{
 			&AlterDatabase{
 				Name: "dbname",

spanner/spansql/types.go

@@ -33,11 +33,12 @@ import (
 // CreateTable represents a CREATE TABLE statement.
 // https://cloud.google.com/spanner/docs/data-definition-language#create_table
 type CreateTable struct {
-	Name        ID
-	Columns     []ColumnDef
-	Constraints []TableConstraint
-	PrimaryKey  []KeyPart
-	Interleave  *Interleave
+	Name              ID
+	Columns           []ColumnDef
+	Constraints       []TableConstraint
+	PrimaryKey        []KeyPart
+	Interleave        *Interleave
+	RowDeletionPolicy *RowDeletionPolicy
 
 	Position Position // position of the "CREATE" token
 }
@@ -90,6 +91,12 @@ type Interleave struct {
 	OnDelete OnDelete
 }
 
+// RowDeletionPolicy represents an row deletion policy clause of a CREATE, ALTER TABLE statement.
+type RowDeletionPolicy struct {
+	Column  ID
+	NumDays int64
+}
+
 // CreateIndex represents a CREATE INDEX statement.
 // https://cloud.google.com/spanner/docs/data-definition-language#create-index
 type CreateIndex struct {
@@ -162,18 +169,22 @@ func (at *AlterTable) clearOffset() {
 }
 
 // TableAlteration is satisfied by AddColumn, DropColumn, AddConstraint,
-// DropConstraint, SetOnDelete and AlterColumn.
+// DropConstraint, SetOnDelete and AlterColumn,
+// AddRowDeletionPolicy, ReplaceRowDeletionPolicy, DropRowDeletionPolicy.
 type TableAlteration interface {
 	isTableAlteration()
 	SQL() string
 }
 
-func (AddColumn) isTableAlteration()      {}
-func (DropColumn) isTableAlteration()     {}
-func (AddConstraint) isTableAlteration()  {}
-func (DropConstraint) isTableAlteration() {}
-func (SetOnDelete) isTableAlteration()    {}
-func (AlterColumn) isTableAlteration()    {}
+func (AddColumn) isTableAlteration()                {}
+func (DropColumn) isTableAlteration()               {}
+func (AddConstraint) isTableAlteration()            {}
+func (DropConstraint) isTableAlteration()           {}
+func (SetOnDelete) isTableAlteration()              {}
+func (AlterColumn) isTableAlteration()              {}
+func (AddRowDeletionPolicy) isTableAlteration()     {}
+func (ReplaceRowDeletionPolicy) isTableAlteration() {}
+func (DropRowDeletionPolicy) isTableAlteration()    {}
 
 type AddColumn struct{ Def ColumnDef }
 type DropColumn struct{ Name ID }
@@ -184,6 +195,9 @@ type AlterColumn struct {
 	Name       ID
 	Alteration ColumnAlteration
 }
+type AddRowDeletionPolicy struct{ RowDeletionPolicy RowDeletionPolicy }
+type ReplaceRowDeletionPolicy struct{ RowDeletionPolicy RowDeletionPolicy }
+type DropRowDeletionPolicy struct{}
 
 // ColumnAlteration is satisfied by SetColumnType and SetColumnOptions.
 type ColumnAlteration interface {