mysql语法

SELECT * FROM t_student  WHERE  1=1 and stu_name LIKE %王%

[Err] 1064 - 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 '%王%' at line 1

注意字符是要带单引号的

SELECT * FROM t_student  WHERE  1=1 and stu_name LIKE '%王%'

if(stuName != null && !stuName.equals("")) {
System.out.println("stuName:"+stuName);
sql.append("and stu_name like ?");
paramList.add("'%"+stuName+"%'");
}

if(stuName != null && !stuName.equals("")) {
System.out.println("stuName:"+stuName);
sql.append("and stu_name like ?");
paramList.add("%"+stuName+"%");
}

USERNAME="root";
PASSWORD="root";
DRIVER="com.mysql.jdbc.Driver";
URL="jdbc:mysql://127.0.0.1:3306/imooc_pager";

  USERNAME="root";
PASSWORD="root";
DRIVER="com.mysql.jdbc.Driver";
URL="jdbc:mysql://127.0.0.1:3306/imooc_pager?useUnicode=true&characterEncoding=utf8";

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 'stu_name like '%王%'and gender = 1' at line 1

StringBuilder sql = new StringBuilder("select * from t_student where 1=1"); //??1=1

if(stuName != null && !stuName.equals("")) {
System.out.println("stuName:"+stuName);
sql.append("and stu_name = ?");
paramList.add("%"+stuName+"%");
}

if(gender == Constant.GENDER_MALE || gender == Constant.GENDER_FEMALE) {
System.out.println("gender:"+gender);
sql.append("and gender = ?");
paramList.add(gender);
}
System.out.println(sql);

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 'stu_name = 'h'and gender = 1' at line 1

StringBuilder sql = new StringBuilder("select * from t_student where 1=1"); // where1=1 后面得加空格跟其他条件隔开

StringBuilder sql = new StringBuilder("select * from t_student where 1=1 ");

类似文章:其他原因的

http://www.itnose.net/detail/982537.html

http://ask.youkuaiyun.com/questions/170059

http://blog.youkuaiyun.com/vanezuo/article/details/6686089

http://blog.sina.com.cn/s/blog_6d70461d01018xul.html

class Y {

public static void main(String[] args) {
String s = "hello";
if(s=="hello") {
System.out.println("==相等hello");
}
if(s.equals("hello")) {
System.out.println("equals相等hello");
}

String snew = new String("new");
if(snew=="new") {
System.out.println("==相等");
}
if(snew.equals("new")) {
System.out.println("equals相等new");
}

//==相等hello
//equals相等hello
//equals相等new
}
}