[release-18.0] Handle Nullability for Columns from Outer Tables (#16174)

go/test/endtoend/vtgate/queries/misc/misc_test.go

@@ -276,3 +276,174 @@ func TestAnalyze(t *testing.T) {
 		})
 	}
 }
+<<<<<<< HEAD
+=======
+
+// TestTransactionModeVar executes SELECT on `transaction_mode` variable
+func TestTransactionModeVar(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 19, "vtgate")
+
+	mcmp, closer := start(t)
+	defer closer()
+
+	tcases := []struct {
+		setStmt string
+		expRes  string
+	}{{
+		expRes: `[[VARCHAR("MULTI")]]`,
+	}, {
+		setStmt: `set transaction_mode = single`,
+		expRes:  `[[VARCHAR("SINGLE")]]`,
+	}, {
+		setStmt: `set transaction_mode = multi`,
+		expRes:  `[[VARCHAR("MULTI")]]`,
+	}, {
+		setStmt: `set transaction_mode = twopc`,
+		expRes:  `[[VARCHAR("TWOPC")]]`,
+	}}
+
+	for _, tcase := range tcases {
+		mcmp.Run(tcase.setStmt, func(mcmp *utils.MySQLCompare) {
+			if tcase.setStmt != "" {
+				utils.Exec(t, mcmp.VtConn, tcase.setStmt)
+			}
+			utils.AssertMatches(t, mcmp.VtConn, "select @@transaction_mode", tcase.expRes)
+		})
+	}
+}
+
+// TestAliasesInOuterJoinQueries tests that aliases work in queries that have outer join clauses.
+func TestAliasesInOuterJoinQueries(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 20, "vtgate")
+
+	mcmp, closer := start(t)
+	defer closer()
+
+	// Insert data into the 2 tables
+	mcmp.Exec("insert into t1(id1, id2) values (1,2), (42,5), (5, 42)")
+	mcmp.Exec("insert into tbl(id, unq_col, nonunq_col) values (1,2,3), (2,5,3), (3, 42, 2)")
+
+	// Check that the select query works as intended and verifying the column names as well.
+	mcmp.ExecWithColumnCompare("select t1.id1 as t0, t1.id1 as t1, tbl.unq_col as col from t1 left outer join tbl on t1.id2 = tbl.nonunq_col")
+	mcmp.ExecWithColumnCompare("select t1.id1 as t0, t1.id1 as t1, tbl.unq_col as col from t1 left outer join tbl on t1.id2 = tbl.nonunq_col order by t1.id2 limit 2")
+	mcmp.ExecWithColumnCompare("select t1.id1 as t0, t1.id1 as t1, tbl.unq_col as col from t1 left outer join tbl on t1.id2 = tbl.nonunq_col order by t1.id2 limit 2 offset 2")
+	mcmp.ExecWithColumnCompare("select t1.id1 as t0, t1.id1 as t1, count(*) as leCount from t1 left outer join tbl on t1.id2 = tbl.nonunq_col group by 1, t1")
+	mcmp.ExecWithColumnCompare("select t.id1, t.id2, derived.unq_col from t1 t join (select id, unq_col, nonunq_col from tbl) as derived on t.id2 = derived.nonunq_col")
+}
+
+func TestAlterTableWithView(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 20, "vtgate")
+	mcmp, closer := start(t)
+	defer closer()
+
+	// Test that create/alter view works and the output is as expected
+	mcmp.Exec(`use ks_misc`)
+	mcmp.Exec(`create view v1 as select * from t1`)
+	var viewDef string
+	utils.WaitForVschemaCondition(t, clusterInstance.VtgateProcess, keyspaceName, func(t *testing.T, ksMap map[string]any) bool {
+		views, ok := ksMap["views"]
+		if !ok {
+			return false
+		}
+		viewsMap := views.(map[string]any)
+		view, ok := viewsMap["v1"]
+		if ok {
+			viewDef = view.(string)
+		}
+		return ok
+	}, "Waiting for view creation")
+	mcmp.Exec(`insert into t1(id1, id2) values (1, 1)`)
+	mcmp.AssertMatches("select * from v1", `[[INT64(1) INT64(1)]]`)
+
+	// alter table add column
+	mcmp.Exec(`alter table t1 add column test bigint`)
+	time.Sleep(10 * time.Second)
+	mcmp.Exec(`alter view v1 as select * from t1`)
+
+	waitForChange := func(t *testing.T, ksMap map[string]any) bool {
+		// wait for the view definition to change
+		views := ksMap["views"]
+		viewsMap := views.(map[string]any)
+		newView := viewsMap["v1"]
+		if newView.(string) == viewDef {
+			return false
+		}
+		viewDef = newView.(string)
+		return true
+	}
+	utils.WaitForVschemaCondition(t, clusterInstance.VtgateProcess, keyspaceName, waitForChange, "Waiting for alter view")
+
+	mcmp.AssertMatches("select * from v1", `[[INT64(1) INT64(1) NULL]]`)
+
+	// alter table remove column
+	mcmp.Exec(`alter table t1 drop column test`)
+	mcmp.Exec(`alter view v1 as select * from t1`)
+
+	utils.WaitForVschemaCondition(t, clusterInstance.VtgateProcess, keyspaceName, waitForChange, "Waiting for alter view")
+
+	mcmp.AssertMatches("select * from v1", `[[INT64(1) INT64(1)]]`)
+}
+
+// TestStraightJoin tests that Vitess respects the ordering of join in a STRAIGHT JOIN query.
+func TestStraightJoin(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 20, "vtgate")
+	mcmp, closer := start(t)
+	defer closer()
+
+	mcmp.Exec("insert into tbl(id, unq_col, nonunq_col) values (1,0,10), (2,10,10), (3,4,20), (4,30,20), (5,40,10)")
+	mcmp.Exec(`insert into t1(id1, id2) values (10, 11), (20, 13)`)
+
+	mcmp.AssertMatchesNoOrder("select tbl.unq_col, tbl.nonunq_col, t1.id2 from t1 join tbl where t1.id1 = tbl.nonunq_col",
+		`[[INT64(0) INT64(10) INT64(11)] [INT64(10) INT64(10) INT64(11)] [INT64(4) INT64(20) INT64(13)] [INT64(40) INT64(10) INT64(11)] [INT64(30) INT64(20) INT64(13)]]`,
+	)
+	// Verify that in a normal join query, vitess joins tbl with t1.
+	res, err := mcmp.VtConn.ExecuteFetch("vexplain plan select tbl.unq_col, tbl.nonunq_col, t1.id2 from t1 join tbl where t1.id1 = tbl.nonunq_col", 100, false)
+	require.NoError(t, err)
+	require.Contains(t, fmt.Sprintf("%v", res.Rows), "tbl_t1")
+
+	// Test the same query with a straight join
+	mcmp.AssertMatchesNoOrder("select tbl.unq_col, tbl.nonunq_col, t1.id2 from t1 straight_join tbl where t1.id1 = tbl.nonunq_col",
+		`[[INT64(0) INT64(10) INT64(11)] [INT64(10) INT64(10) INT64(11)] [INT64(4) INT64(20) INT64(13)] [INT64(40) INT64(10) INT64(11)] [INT64(30) INT64(20) INT64(13)]]`,
+	)
+	// Verify that in a straight join query, vitess joins t1 with tbl.
+	res, err = mcmp.VtConn.ExecuteFetch("vexplain plan select tbl.unq_col, tbl.nonunq_col, t1.id2 from t1 straight_join tbl where t1.id1 = tbl.nonunq_col", 100, false)
+	require.NoError(t, err)
+	require.Contains(t, fmt.Sprintf("%v", res.Rows), "t1_tbl")
+}
+
+func TestColumnAliases(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 20, "vtgate")
+	mcmp, closer := start(t)
+	defer closer()
+
+	mcmp.Exec("insert into t1(id1, id2) values (0,0), (1,1)")
+	mcmp.ExecWithColumnCompare(`select a as k from (select count(*) as a from t1) t`)
+}
+
+func TestHandleNullableColumn(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 21, "vtgate")
+	require.NoError(t,
+		utils.WaitForAuthoritative(t, keyspaceName, "tbl", clusterInstance.VtgateProcess.ReadVSchema))
+	mcmp, closer := start(t)
+	defer closer()
+
+	mcmp.Exec("insert into t1(id1, id2) values (0,0), (1,1), (2,2)")
+	mcmp.Exec("insert into tbl(id, unq_col, nonunq_col) values (0,0,0), (1,1,6)")
+	// This query tests that we handle nullable columns correctly
+	// tbl.nonunq_col is not nullable according to the schema, but because of the left join, it can be NULL
+	mcmp.ExecWithColumnCompare(`select * from t1 left join tbl on t1.id2 = tbl.id where t1.id1 = 6 or tbl.nonunq_col = 6`)
+}
+
+func TestEnumSetVals(t *testing.T) {
+	utils.SkipIfBinaryIsBelowVersion(t, 20, "vtgate")
+
+	mcmp, closer := start(t)
+	defer closer()
+	require.NoError(t, utils.WaitForAuthoritative(t, keyspaceName, "tbl_enum_set", clusterInstance.VtgateProcess.ReadVSchema))
+
+	mcmp.Exec("insert into tbl_enum_set(id, enum_col, set_col) values (1, 'medium', 'a,b,e'), (2, 'small', 'e,f,g'), (3, 'large', 'c'), (4, 'xsmall', 'a,b'), (5, 'medium', 'a,d')")
+
+	mcmp.AssertMatches("select id, enum_col, cast(enum_col as signed) from tbl_enum_set order by enum_col, id", `[[INT64(4) ENUM("xsmall") INT64(1)] [INT64(2) ENUM("small") INT64(2)] [INT64(1) ENUM("medium") INT64(3)] [INT64(5) ENUM("medium") INT64(3)] [INT64(3) ENUM("large") INT64(4)]]`)
+	mcmp.AssertMatches("select id, set_col, cast(set_col as unsigned) from tbl_enum_set order by set_col, id", `[[INT64(4) SET("a,b") UINT64(3)] [INT64(3) SET("c") UINT64(4)] [INT64(5) SET("a,d") UINT64(9)] [INT64(1) SET("a,b,e") UINT64(19)] [INT64(2) SET("e,f,g") UINT64(112)]]`)
+}
+>>>>>>> 5a6f3868c5 (Handle Nullability for Columns from Outer Tables (#16174))

go/test/endtoend/vtgate/queries/misc/schema.sql

@@ -1,5 +1,46 @@
+<<<<<<< HEAD
 create table if not exists t1(
                    id1 bigint,
                    id2 bigint,
                    primary key(id1)
-) Engine=InnoDB;
+) Engine=InnoDB;
+=======
+create table t1
+(
+    id1 bigint,
+    id2 bigint,
+    primary key (id1)
+) Engine=InnoDB;
+
+create table unq_idx
+(
+    unq_col     bigint,
+    keyspace_id varbinary(20),
+    primary key (unq_col)
+) Engine = InnoDB;
+
+create table nonunq_idx
+(
+    nonunq_col  bigint,
+    id          bigint,
+    keyspace_id varbinary(20),
+    primary key (nonunq_col, id)
+) Engine = InnoDB;
+
+create table tbl
+(
+    id         bigint,
+    unq_col    bigint,
+    nonunq_col bigint not null,
+    primary key (id),
+    unique (unq_col)
+) Engine = InnoDB;
+
+create table tbl_enum_set
+(
+    id       bigint,
+    enum_col enum('xsmall', 'small', 'medium', 'large', 'xlarge'),
+    set_col set('a', 'b', 'c', 'd', 'e', 'f', 'g'),
+    primary key (id)
+) Engine = InnoDB;
+>>>>>>> 5a6f3868c5 (Handle Nullability for Columns from Outer Tables (#16174))

go/vt/vtgate/evalengine/compiler.go

@@ -50,7 +50,135 @@ type ctype struct {
 	Col  collations.TypedCollation
 }
 
+<<<<<<< HEAD
 func (ct ctype) nullable() bool {
+=======
+type Type struct {
+	typ         sqltypes.Type
+	collation   collations.ID
+	nullable    bool
+	init        bool
+	size, scale int32
+	values      *EnumSetValues
+}
+
+func (v *EnumSetValues) Equal(other *EnumSetValues) bool {
+	if v == nil && other == nil {
+		return true
+	}
+	if v == nil || other == nil {
+		return false
+	}
+	return slices.Equal(*v, *other)
+}
+
+func NewType(t sqltypes.Type, collation collations.ID) Type {
+	// New types default to being nullable
+	return NewTypeEx(t, collation, true, 0, 0, nil)
+}
+
+func NewTypeEx(t sqltypes.Type, collation collations.ID, nullable bool, size, scale int32, values *EnumSetValues) Type {
+	return Type{
+		typ:       t,
+		collation: collation,
+		nullable:  nullable,
+		init:      true,
+		size:      size,
+		scale:     scale,
+		values:    values,
+	}
+}
+
+func NewTypeFromField(f *querypb.Field) Type {
+	return Type{
+		typ:       f.Type,
+		collation: collations.ID(f.Charset),
+		nullable:  f.Flags&uint32(querypb.MySqlFlag_NOT_NULL_FLAG) == 0,
+		init:      true,
+		size:      int32(f.ColumnLength),
+		scale:     int32(f.Decimals),
+	}
+}
+
+func (t *Type) ToField(name string) *querypb.Field {
+	// need to get the proper flags for the type; usually leaving flags
+	// to 0 is OK, because Vitess' MySQL client will generate the right
+	// ones for the column's type, but here we're also setting the NotNull
+	// flag, so it needs to be set with the full flags for the column
+	_, flags := sqltypes.TypeToMySQL(t.typ)
+	if !t.nullable {
+		flags |= int64(querypb.MySqlFlag_NOT_NULL_FLAG)
+	}
+
+	f := &querypb.Field{
+		Name:         name,
+		Type:         t.typ,
+		Charset:      uint32(t.collation),
+		ColumnLength: uint32(t.size),
+		Decimals:     uint32(t.scale),
+		Flags:        uint32(flags),
+	}
+	return f
+}
+
+func (t *Type) Type() sqltypes.Type {
+	if t.init {
+		return t.typ
+	}
+	return sqltypes.Unknown
+}
+
+func (t *Type) Collation() collations.ID {
+	return t.collation
+}
+
+func (t *Type) Size() int32 {
+	return t.size
+}
+
+func (t *Type) Scale() int32 {
+	return t.scale
+}
+
+func (t *Type) Nullable() bool {
+	if t.init {
+		return t.nullable
+	}
+	return true // nullable by default for unknown types
+}
+
+func (t *Type) SetNullability(n bool) {
+	t.nullable = n
+}
+
+func (t *Type) Values() *EnumSetValues {
+	return t.values
+}
+
+func (t *Type) Valid() bool {
+	return t.init
+}
+
+func (t *Type) Equal(other *Type) bool {
+	return t.typ == other.typ &&
+		t.collation == other.collation &&
+		t.nullable == other.nullable &&
+		t.size == other.size &&
+		t.scale == other.scale &&
+		t.values.Equal(other.values)
+}
+
+func (ct *ctype) equal(other ctype) bool {
+	return ct.Type == other.Type &&
+		ct.Flag == other.Flag &&
+		ct.Size == other.Size &&
+		ct.Scale == other.Scale &&
+		ct.Col == other.Col &&
+		ct.Values.Equal(other.Values)
+}
+
+func (ct *ctype) nullable() bool {
+>>>>>>> 5a6f3868c5 (Handle Nullability for Columns from Outer Tables (#16174))
 	return ct.Flag&flagNullable != 0
 }