如下的一个普通JDBC示例:
String user ="root";
String password = "root";
String url = "jdbc:mysql://localhost:3306";
Connection conn = java.sql.DriverManager.getConnection(url , user, password);
Statement stmt = conn.createStatement();
String sql = "select 'hello';select 'world'";
stmt.execute(sql);
执行时会报错:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'select 'world'' at line 1at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
若一个sql中通过分号分割(或包含)了多个独立sql的话，如:
select 'hello';select 'world'
默认就会报上述错误,当若显式设置allowMultiQueries为true的话,就可以正常执行不会报错.如下所示:
String url = "jdbc:mysql://localhost:3306?allowMultiQueries=true";
allowMultiQueries
Allow the use of ';' to delimit multiple queries during one statement (true/false), defaults to 'false', and does not affect the addBatch() and executeBatch() methods, which instead rely on rewriteBatchStatements.
Default: false
Since version: 3.1.1