bug fixed for mysql parser. for issue #2388

src/main/java/com/alibaba/druid/sql/parser/Lexer.java

@@ -1102,6 +1102,12 @@ public class Lexer {
                     case '\\':
                         putChar('\\');
                         break;
+                    case '_':
+                        if(JdbcConstants.MYSQL.equals(dbType)) {
+                            putChar('\\');
+                        }
+                        putChar('_');
+                        break;
                     case 'Z':
                         putChar((char) 0x1A); // ctrl + Z
                         break;

src/test/java/com/alibaba/druid/bvt/sql/mysql/insert/MySqlInsertTest_26_special.java

@@ -0,0 +1,59 @@
+/*
+ * Copyright 1999-2017 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.bvt.sql.mysql.insert;
+
+import com.alibaba.druid.sql.MysqlTest;
+import com.alibaba.druid.sql.SQLUtils;
+import com.alibaba.druid.sql.ast.SQLStatement;
+import com.alibaba.druid.sql.dialect.mysql.ast.statement.MySqlInsertStatement;
+import com.alibaba.druid.sql.dialect.mysql.parser.MySqlStatementParser;
+import com.alibaba.druid.sql.visitor.ParameterizedOutputVisitorUtils;
+import com.alibaba.druid.util.JdbcConstants;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class MySqlInsertTest_26_special extends MysqlTest {
+
+    public void test_insert_timestamp() throws Exception {
+        String sql = "INSERT INTO SUNTEST(ID,NAME) VALUES(1,'\\_ASDFASDF')";
+
+        {
+            List<Object> outParameters = new ArrayList<Object>();
+            String psql = ParameterizedOutputVisitorUtils.parameterize(sql, JdbcConstants.MYSQL, outParameters);
+            assertEquals("INSERT INTO SUNTEST(ID, NAME)\n" +
+                    "VALUES (?, ?)", psql);
+
+            assertEquals(2, outParameters.size());
+
+            String rsql = ParameterizedOutputVisitorUtils.restore(psql, JdbcConstants.MYSQL, outParameters);
+            assertEquals("INSERT INTO SUNTEST (ID, NAME)\n" +
+                    "VALUES (1, '\\\\_ASDFASDF')", rsql);
+        }
+
+        MySqlStatementParser parser = new MySqlStatementParser(sql);
+        List<SQLStatement> statementList = parser.parseStatementList();
+        SQLStatement stmt = statementList.get(0);
+
+        MySqlInsertStatement insertStmt = (MySqlInsertStatement) stmt;
+
+        assertEquals("INSERT INTO SUNTEST (ID, NAME)\n" +
+                "VALUES (1, '\\\\_ASDFASDF')", SQLUtils.toMySqlString(insertStmt));
+
+
+    }
+
+}