mysql 批量插入数据如何防止重复插入

mysql批量插入数据时,会存在重复数据的可能.
可以通过1)数据库加联合索引
2)修改sql,忽略重复的数据,防止数据库报错
1.

CREATE TABLE `merchantBlackList` (
  `id` int(5) NOT NULL AUTO_INCREMENT,
  `createTime` datetime NOT NULL,
  `bankId` int(10) DEFAULT NULL COMMENT '银行id',
  `merchantSn` varchar(20) COLLATE utf8mb4_unicode_ci DEFAULT NULL COMMENT '商户编号',
  PRIMARY KEY (`id`),
  UNIQUE KEY `bankId_merchantSn` (`bankId`,`merchantSn`)//联合索引
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

2.

<insert id="batchInsert"  parameterType="ArrayList">
        INSERT INTO merchantBlackList(createTime,bankId,merchantSn)
        VALUES
        <foreach collection="list" item="item" index="index" separator="," >
            (#{item.createTime},#{item.bankId},#{item.merchantSn})
        </foreach>
        ON DUPLICATE KEY UPDATE
        bankId=VALUES(bankId),
        merchantSn=VALUES(merchantSn);
    </insert>

本文地址：https://blog.csdn.net/java_zhulinghai/article/details/107404863