parser: parse decimal literal instead of float literal (pingcap#2044)

Improves MySQL compatibility.
anywhy · Nov 21, 2016 · 91050ff · 91050ff
1 parent 8475658
commit 91050ff
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Showing 8 changed files with 35 additions and 7 deletions.
diff --git a/ddl/ddl.go b/ddl/ddl.go
@@ -595,7 +595,10 @@ func getDefaultValue(ctx context.Context, c *ast.ColumnOption, tp byte, fsp int)
 	if err != nil {
 		return nil, errors.Trace(err)
 	}
-	return v.GetValue(), nil
+	if v.IsNull() {
+		return nil, nil
+	}
+	return v.ToString()
 }
 
 func removeOnUpdateNowFlag(c *table.Column) {

diff --git a/executor/show_test.go b/executor/show_test.go
@@ -61,7 +61,7 @@ func (s *testSuite) TestShow(c *C) {
 	c.Check(result.Rows(), HasLen, 1)
 	row = result.Rows()[0]
 	expectedRow = []interface{}{
-		"ptest", "CREATE TABLE `ptest` (\n  `a` int(11) NOT NULL,\n  `b` double NOT NULL DEFAULT '2',\n  `c` varchar(10) NOT NULL,\n  `d` time DEFAULT NULL,\n  `e` timestamp NULL DEFAULT NULL,\n PRIMARY KEY (`a`),\n  UNIQUE KEY `d` (`d`)\n) ENGINE=InnoDB"}
+		"ptest", "CREATE TABLE `ptest` (\n  `a` int(11) NOT NULL,\n  `b` double NOT NULL DEFAULT '2.0',\n  `c` varchar(10) NOT NULL,\n  `d` time DEFAULT NULL,\n  `e` timestamp NULL DEFAULT NULL,\n PRIMARY KEY (`a`),\n  UNIQUE KEY `d` (`d`)\n) ENGINE=InnoDB"}
 	for i, r := range row {
 		c.Check(r, Equals, expectedRow[i])
 	}

diff --git a/parser/lexer.go b/parser/lexer.go
@@ -102,6 +102,8 @@ func (s *Scanner) Lex(v *yySymType) int {
 		return toInt(s, v, lit)
 	case floatLit:
 		return toFloat(s, v, lit)
+	case decLit:
+		return toDecimal(s, v, lit)
 	case hexLit:
 		return toHex(s, v, lit)
 	case bitLit:
@@ -520,9 +522,16 @@ func (s *Scanner) scanFloat(beg *Pos) (tok int, pos Pos, lit string) {
 	}
 	if ch0 == 'e' || ch0 == 'E' {
 		s.r.inc()
+		ch0 = s.r.peek()
+		if ch0 == '-' || ch0 == '+' {
+			s.r.inc()
+		}
 		s.scanDigits()
+		tok = floatLit
+	} else {
+		tok = decLit
 	}
-	tok, pos, lit = floatLit, *beg, s.r.data(beg)
+	pos, lit = *beg, s.r.data(beg)
 	return
 }
 

diff --git a/parser/lexer_test.go b/parser/lexer_test.go
@@ -15,10 +15,10 @@ package parser
 
 import (
 	"fmt"
+	"unicode"
 
 	. "github.com/pingcap/check"
 	"github.com/pingcap/tidb/util/testleak"
-	"unicode"
 )
 
 var _ = Suite(&testLexerSuite{})
@@ -92,8 +92,10 @@ func (s *testLexerSuite) TestLiteral(c *C) {
 		{`""a""`, stringLit},
 		{`\'a\'`, int('\\')},
 		{`\"a\"`, int('\\')},
-		{"0.2314", floatLit},
+		{"0.2314", decLit},
+		{"132.313", decLit},
 		{"132.3e231", floatLit},
+		{"132.3e-231", floatLit},
 		{"23416", intLit},
 		{"123test", identifier},
 		{"123" + string(unicode.ReplacementChar) + "xxx", identifier},

diff --git a/parser/parser.y b/parser/parser.y
@@ -382,6 +382,7 @@ import (
 %token	<item>
 
 	/*yy:token "1.%d"   */	floatLit        "floating-point literal"
+	/*yy:token "1.%d"   */	decLit          "decimal literal"
 	/*yy:token "%d"     */	intLit          "integer literal"
 	/*yy:token "%x"     */	hexLit          "hexadecimal literal"
 	/*yy:token "%b"     */	bitLit          "bit literal"
@@ -1276,6 +1277,7 @@ SignedLiteral:
 NumLiteral:
 	intLit
 |	floatLit
+|	decLit
 
 
 CreateIndexStmt:
@@ -2192,6 +2194,7 @@ Literal:
 		$$ = int64(1)
 	}
 |	floatLit
+|	decLit
 |	intLit
 |	stringLit
 	{

diff --git a/parser/yy_parser.go b/parser/yy_parser.go
@@ -23,6 +23,7 @@ import (
 	"github.com/pingcap/tidb/ast"
 	"github.com/pingcap/tidb/mysql"
 	"github.com/pingcap/tidb/terror"
+	"github.com/pingcap/tidb/util/hack"
 )
 
 // Error instances.
@@ -151,6 +152,16 @@ func toInt(l yyLexer, lval *yySymType, str string) int {
 	return intLit
 }
 
+func toDecimal(l yyLexer, lval *yySymType, str string) int {
+	dec := new(mysql.MyDecimal)
+	err := dec.FromString(hack.Slice(str))
+	if err != nil {
+		l.Errorf("decimal literal: %v", err)
+	}
+	lval.item = dec
+	return decLit
+}
+
 func toFloat(l yyLexer, lval *yySymType, str string) int {
 	n, err := strconv.ParseFloat(str, 64)
 	if err != nil {

diff --git a/server/driver_tidb.go b/server/driver_tidb.go
@@ -212,7 +212,7 @@ func (tc *TiDBContext) Auth(user string, auth []byte, salt []byte) bool {
 
 // FieldList implements IContext FieldList method.
 func (tc *TiDBContext) FieldList(table string) (colums []*ColumnInfo, err error) {
-	rs, err := tc.Execute("SELECT * FROM " + table + " LIMIT 0")
+	rs, err := tc.Execute("SELECT * FROM `" + table + "` LIMIT 0")
 	if err != nil {
 		return nil, errors.Trace(err)
 	}

diff --git a/util/types/datum.go b/util/types/datum.go
@@ -958,7 +958,7 @@ func (d *Datum) convertToMysqlDecimal(target *FieldType) (Datum, error) {
 	case KindString, KindBytes:
 		err = dec.FromString(d.GetBytes())
 	case KindMysqlDecimal:
-		dec = d.GetMysqlDecimal()
+		*dec = *d.GetMysqlDecimal()
 	case KindMysqlTime:
 		dec = d.GetMysqlTime().ToNumber()
 	case KindMysqlDuration: