Merge pull request #133184 from cockroachdb/blathers/backport-release…

…-24.1-132944

release-24.1: sql: add `BIT(0)` type

pkg/sql/logictest/testdata/logic_test/drop_function

@@ -365,3 +365,27 @@ CREATE FUNCTION f_char(c BPCHAR) RETURNS INT LANGUAGE SQL AS 'SELECT 1'
 
 statement ok
 DROP FUNCTION f_char(CHAR(2))
+
+statement ok
+CREATE FUNCTION f_bit(c BIT) RETURNS INT LANGUAGE SQL AS 'SELECT 1'
+
+statement ok
+DROP FUNCTION f_bit(BIT(0))
+
+statement ok
+CREATE FUNCTION f_bit(c BIT(2)) RETURNS INT LANGUAGE SQL AS 'SELECT 1'
+
+statement ok
+DROP FUNCTION f_bit(BIT(0))
+
+statement ok
+CREATE FUNCTION f_bit(c BIT(0)) RETURNS INT LANGUAGE SQL AS 'SELECT 1'
+
+statement ok
+DROP FUNCTION f_bit(BIT(0))
+
+statement ok
+CREATE FUNCTION f_bit(c BIT(0)) RETURNS INT LANGUAGE SQL AS 'SELECT 1'
+
+statement ok
+DROP FUNCTION f_bit(BIT(2))

pkg/sql/logictest/testdata/logic_test/typing

@@ -310,6 +310,69 @@ WHERE t108360_1.t = (CASE WHEN t108360_1.t > t108360_2.c THEN t108360_1.t ELSE t
 ----
 tt
 
+# Regression test for #131346. Ensure CASE is typed correctly and that a cast to
+# the BIT type with an unspecified length behaves correctly during distributed
+# execution.
+statement ok
+CREATE TABLE t131346v (v VARBIT);
+INSERT INTO t131346v VALUES ('11');
+
+statement ok
+CREATE TABLE t131346b (b BIT);
+INSERT INTO t131346b VALUES ('0');
+
+query T
+SELECT v FROM t131346v, t131346b
+WHERE v NOT BETWEEN v AND
+  (CASE WHEN NULL THEN '0'::BIT ELSE v END)
+----
+
+query T
+SELECT v FROM t131346v, t131346b
+WHERE v NOT BETWEEN v AND
+  (CASE WHEN NULL THEN b ELSE v END)
+----
+
+query T
+SELECT v FROM t131346v, t131346b
+WHERE v NOT BETWEEN v AND
+  IF(NULL, '0'::BIT, v);
+----
+
+query T
+SELECT v FROM t131346v, t131346b
+WHERE v NOT BETWEEN v AND
+  IF(NULL, b, v);
+----
+
+query T
+SELECT (CASE WHEN v > '0'::BIT THEN v ELSE '0'::BIT END)
+FROM t131346v, t131346b
+WHERE v = (CASE WHEN v > '0'::BIT THEN v ELSE '0'::BIT END)
+----
+11
+
+query T
+SELECT (CASE WHEN v > b THEN v ELSE b END)
+FROM t131346v, t131346b
+WHERE v = (CASE WHEN v > b THEN v ELSE b END)
+----
+11
+
+query T
+SELECT (CASE WHEN v > '0'::BIT THEN v ELSE '0'::BIT END)
+FROM t131346v, t131346b
+WHERE v = (CASE WHEN v < '0'::BIT THEN '0'::BIT ELSE v END)
+----
+11
+
+query T
+SELECT (CASE WHEN v > b THEN v ELSE b END)
+FROM t131346v, t131346b
+WHERE v = (CASE WHEN v < b THEN b ELSE v END)
+----
+11
+
 # Static analysis types should never make it to execution.
 statement ok
 CREATE TABLE t83496 (

pkg/sql/opt/optbuilder/scalar.go

@@ -244,6 +244,8 @@ func (b *Builder) buildScalar(
 		for i := range t.Whens {
 			condExpr := t.Whens[i].Cond.(tree.TypedExpr)
 			cond := b.buildScalar(condExpr, inScope, nil, nil, colRefs)
+			// TODO(mgartner): Rather than use WithoutTypeModifiers here,
+			// consider typing the CaseExpr without a type modifier.
 			valExpr, ok := eval.ReType(t.Whens[i].Val.(tree.TypedExpr), valType.WithoutTypeModifiers())
 			if !ok {
 				panic(pgerror.Newf(

pkg/sql/parser/parse.go

@@ -412,17 +412,18 @@ func GetTypeFromCastOrCollate(expr tree.Expr) (tree.ResolvableTypeReference, err
 	return cast.Type, nil
 }
 
-var errBitLengthNotPositive = pgerror.WithCandidateCode(
-	errors.New("length for type bit must be at least 1"), pgcode.InvalidParameterValue)
+var errVarBitLengthNotPositive = pgerror.WithCandidateCode(
+	errors.New("length for type varbit must be at least 1"), pgcode.InvalidParameterValue)
 
 // newBitType creates a new BIT type with the given bit width.
 func newBitType(width int32, varying bool) (*types.T, error) {
-	if width < 1 {
-		return nil, errBitLengthNotPositive
-	}
 	if varying {
+		if width < 1 {
+			return nil, errVarBitLengthNotPositive
+		}
 		return types.MakeVarBit(width), nil
 	}
+	// The iconst32 pattern in the parser guarantees that the width is positive.
 	return types.MakeBit(width), nil
 }
 

pkg/sql/parser/testdata/create_table

@@ -176,23 +176,24 @@ CREATE TABLE foo(a CHAR(0))
                          ^
 
 parse
-CREATE TABLE a (b BIT VARYING(2), c BIT(1))
+CREATE TABLE a (b BIT VARYING(2), c BIT(1), c BIT, c BIT(0))
 ----
-CREATE TABLE a (b VARBIT(2), c BIT) -- normalized!
-CREATE TABLE a (b VARBIT(2), c BIT) -- fully parenthesized
-CREATE TABLE a (b VARBIT(2), c BIT) -- literals removed
-CREATE TABLE _ (_ VARBIT(2), _ BIT) -- identifiers removed
+CREATE TABLE a (b VARBIT(2), c BIT, c BIT, c BIT(0)) -- normalized!
+CREATE TABLE a (b VARBIT(2), c BIT, c BIT, c BIT(0)) -- fully parenthesized
+CREATE TABLE a (b VARBIT(2), c BIT, c BIT, c BIT(0)) -- literals removed
+CREATE TABLE _ (_ VARBIT(2), _ BIT, _ BIT, _ BIT(0)) -- identifiers removed
 
 error
 CREATE TABLE test (
-  foo BIT(0)
+  foo BIT(-1)
 )
 ----
-at or near ")": syntax error: length for type bit must be at least 1
+at or near "-": syntax error
 DETAIL: source SQL:
 CREATE TABLE test (
-  foo BIT(0)
-           ^
+  foo BIT(-1)
+          ^
+HINT: try \h CREATE TABLE
 
 
 parse

pkg/sql/parser/testdata/select_exprs

@@ -952,6 +952,14 @@ SELECT (('foo')::DECIMAL(2,1)) -- fully parenthesized
 SELECT '_'::DECIMAL(2,1) -- literals removed
 SELECT 'foo'::DECIMAL(2,1) -- identifiers removed
 
+parse
+SELECT 'foo'::BIT
+----
+SELECT 'foo'::BIT
+SELECT (('foo')::BIT) -- fully parenthesized
+SELECT '_'::BIT -- literals removed
+SELECT 'foo'::BIT -- identifiers removed
+
 parse
 SELECT 'foo'::BIT(3)
 ----
@@ -960,6 +968,14 @@ SELECT (('foo')::BIT(3)) -- fully parenthesized
 SELECT '_'::BIT(3) -- literals removed
 SELECT 'foo'::BIT(3) -- identifiers removed
 
+parse
+SELECT 'foo'::BIT(0)
+----
+SELECT 'foo'::BIT(0)
+SELECT (('foo')::BIT(0)) -- fully parenthesized
+SELECT '_'::BIT(0) -- literals removed
+SELECT 'foo'::BIT(0) -- identifiers removed
+
 parse
 SELECT 'foo'::VARBIT(3)
 ----

pkg/sql/sem/cast/type_name.go

@@ -28,6 +28,9 @@ func CastTypeName(t *types.T) string {
 	case oid.T_text:
 		// SQLString returns `string`
 		return "text"
+	case oid.T_bit:
+		// SQLString returns `decimal`
+		return "bit"
 	}
 	return strings.ToLower(t.SQLString())
 }

pkg/sql/sem/tree/col_types_test.go

@@ -25,6 +25,7 @@ func TestParseColumnType(t *testing.T) {
 		expectedType *types.T
 	}{
 		{"BIT", types.MakeBit(1)},
+		{"BIT(0)", types.MakeBit(0)},
 		{"VARBIT", types.MakeVarBit(0)},
 		{"BIT(2)", types.MakeBit(2)},
 		{"VARBIT(2)", types.MakeVarBit(2)},

pkg/sql/sem/tree/overload.go

@@ -492,7 +492,10 @@ func (p ParamTypes) MatchAtIdentical(typ *types.T, i int) bool {
 		p[i].Typ.Identical(typ) ||
 		// Special case for CHAR, CHAR(N), and BPCHAR which are not "identical"
 		// but have the same OID. See #129007.
-		(p[i].Typ.Oid() == oid.T_bpchar && typ.Oid() == oid.T_bpchar))
+		(p[i].Typ.Oid() == oid.T_bpchar && typ.Oid() == oid.T_bpchar) ||
+		// Special case for BIT, BIT(N), and BIT(0) which are not "identical"
+		// but have the same OID. See #132944.
+		(p[i].Typ.Oid() == oid.T_bit && typ.Oid() == oid.T_bit))
 }
 
 // MatchLen is part of the TypeList interface.

pkg/sql/types/types.go

@@ -115,6 +115,7 @@ import (
 // | FLOAT4            | FLOAT          | T_float4      | 0         | 0     |
 // |                   |                |               |           |       |
 // | BIT               | BIT            | T_bit         | 0         | 1     |
+// | BIT(0)            | BIT            | T_bit         | 0         | 0     |
 // | BIT(N)            | BIT            | T_bit         | 0         | N     |
 // | VARBIT            | BIT            | T_varbit      | 0         | 0     |
 // | VARBIT(N)         | BIT            | T_varbit      | 0         | N     |
@@ -698,9 +699,10 @@ var (
 
 // Unexported wrapper types.
 var (
-	// typeBit is the SQL BIT type. It is not exported to avoid confusion with
-	// the VarBit type, and confusion over whether its default Width is
-	// unspecified or is 1. More commonly used instead is the VarBit type.
+	// typeBit is the SQL BIT type with an unspecified width. It is not exported
+	// to avoid confusion with the VarBit type, and confusion over whether its
+	// default Width is unspecified or is 1. More commonly used instead is the
+	// VarBit type.
 	typeBit = &T{InternalType: InternalType{
 		Family: BitFamily, Oid: oid.T_bit, Locale: &emptyLocale}}
 
@@ -1888,17 +1890,27 @@ func (t *T) InformationSchemaName() string {
 func (t *T) SQLString() string {
 	switch t.Family() {
 	case BitFamily:
-		o := t.Oid()
-		typName := "BIT"
-		if o == oid.T_varbit {
-			typName = "VARBIT"
-		}
-		// BIT(1) pretty-prints as just BIT.
-		if (o != oid.T_varbit && t.Width() > 1) ||
-			(o == oid.T_varbit && t.Width() > 0) {
-			typName = fmt.Sprintf("%s(%d)", typName, t.Width())
+		switch t.Oid() {
+		case oid.T_bit:
+			typName := "BIT"
+			// BIT(1) pretty-prints as just BIT.
+			// BIT(0) represents a BIT type with unspecified length. This is a
+			// divergence from Postgres which does not allow this type and has
+			// no way to represent it in SQL. It is required in order for it to
+			// be correctly serialized into SQL and evaluated during distributed
+			// query execution. VARBIT cannot be used because it has a different
+			// OID.
+			if t.Width() != 1 {
+				typName = fmt.Sprintf("%s(%d)", typName, t.Width())
+			}
+			return typName
+		default:
+			typName := "VARBIT"
+			if t.Width() > 0 {
+				typName = fmt.Sprintf("%s(%d)", typName, t.Width())
+			}
+			return typName
 		}
-		return typName
 	case IntFamily:
 		switch t.Width() {
 		case 16: