fix parseDDL bug with escaped quote (#89)

ddlmod.go

@@ -32,15 +32,19 @@ func parseDDL(strs ...string) (*ddl, error) {
 		if sections := tableRegexp.FindStringSubmatch(str); len(sections) > 0 {
 			var (
 				ddlBody      = sections[2]
+				ddlBodyRunes = []rune(ddlBody)
 				bracketLevel int
 				quote        rune
 				buf          string
 			)
 
 			result.head = sections[1]
 
-			for idx, c := range []rune(ddlBody) {
-				var next rune = 0
+			for idx := 0; idx < len(ddlBodyRunes); idx++ {
+				var (
+					next rune = 0
+					c         = ddlBodyRunes[idx]
+				)
 				if idx+1 < len(ddlBody) {
 					next = []rune(ddlBody)[idx+1]
 				}

ddlmod_test.go

@@ -180,6 +180,11 @@ func TestGetColumns(t *testing.T) {
 			ddl:     "CREATE TABLE Persons (ID int NOT NULL,LastName varchar(255) NOT NULL,FirstName varchar(255),Age int,CHECK (Age>=18),CHECK (FirstName!='John'))",
 			columns: []string{"`ID`", "`LastName`", "`FirstName`", "`Age`"},
 		},
+		{
+			name:    "with_escaped_quote",
+			ddl:     "CREATE TABLE Persons (ID int NOT NULL,LastName varchar(255) NOT NULL DEFAULT \"\",FirstName varchar(255))",
+			columns: []string{"`ID`", "`LastName`", "`FirstName`"},
+		},
 	}
 
 	for _, p := range params {