解决mysqldump备份报错： Couldn't execute 'SHOW FIELDS FROM Unknown error 1356

服务器环境：

1. [[email protected] mysql]# cat /etc/redhat-release
   CentOS Linux release 7.3.1611 (Core)
   [[email protected] mysql]# uname -a
   Linux localhost.localdomain 3.10.0-514.21.1.el7.x86_64 #1 SMP Thu May 25 17:04:51 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
   [[email protected] mysql]# CentOS Linux release 7.3.1611 (Core)

MySQL版本号：

mysql> select version();
+------------+
| version()  |
+------------+
| 5.7.13-log |
+------------+
1 row in set (0.00 sec)

报错具体情况：

1. [[email protected] tmp]# mysqldump -uroot -p --default-character-set=utf8  --triggers -R --hex-blob --flush-logs  --events --single-transaction  --master-data=2  --all-databases|gzip >/tmp/134-20170831.sql.gz  
   Enter password:
   mysqldump: Couldn‘t execute ‘SHOW FIELDS FROM `v_product_info`‘: Unknown error 1356 (1356)

之前，由于数据库作主要用于测试，数据量不大，所以直接用的是mysqldump备份，没有出过问题。今天根据报错提示，是`v_product_info`这个视图出了问题；

下面排查问题所在：

1. mysql> select * from information_schema.tables where TABLE_NAME LIKE ‘%v_product_info%‘ AND table_type=‘view‘\G;

   mysql> USE POSEIDON;

   mysql> SHOW CREATE  VIEW v_product_info\G;

2. 下面为视图内容：
   CREATE ALGORITHM = UNDEFINED DEFINER = `dev_oheimdall_user`@`%` SQL SECURITY DEFINER VIEW `v_product_info` AS SELECT
       `a`.`id` AS `id`,
       `a`.`product_name` AS `product_name`,
       `a`.`feechannel_name` AS `feechannel_name`,
       `d`.`branch` AS `branch`,
       `a`.`product_city` AS `product_city`,
       `a`.`product_type` AS `product_type`,
       `a`.`mortgage_lend_terms` AS `mortgage_lend_terms`,
       `c`.`sparehouse_require` AS `sparehouse_require`,
       `a`.`lend_time_start` AS `lend_time_start`,
       `a`.`lend_time_end` AS `lend_time_end`,
       `a`.`month_rate_start` AS `month_rate_start`,
       `a`.`month_rate_end` AS `month_rate_end`,
       `a`.`repayment_mode` AS `repayment_mode`,
       `a`.`gmt_create` AS `gmt_create`,
       `a`.`status_name` AS `status_name`,
       `a`.`creater` AS `creater`,
       (
           CASE
           WHEN (
               `a`.`id` = `b`.`product_basic_id`
           ) THEN
               `b`.`credit`
           WHEN (
               `a`.`id` = `c`.`product_basic_id`
           ) THEN
               `c`.`credit_require`
           END
       ) AS `credit`
   FROM
       (
           (
               (
                   `product_basic` `a`
                   LEFT JOIN `product_credit_admit` `b` ON (
                       (
                           `a`.`id` = `b`.`product_basic_id`
                       )
                   )
               )
               LEFT JOIN `product_mortgage_admit` `c` ON (
                   (
                       `a`.`id` = `c`.`product_basic_id`
                   )
               )
           )
           LEFT JOIN `fund_channel` `d` ON (
               (
                   `a`.`feechannel_id` = `d`.`id`
               )
           )
       )

解决问题办法：

1. 处理办法：
   mysql> DESC product_basic;
   ERROR 1146 (42S02): Unknown error 1146
   mysql> DESC product_mortgage_admit;
   ERROR 1146 (42S02): Unknown error 1146
   mysql> DROP VIEW v_product_info;
   Query OK, 0 rows affected (0.10 sec)

然后再进行备份，发现很快顺利完成。

解决mysqldump备份报错： Couldn't execute 'SHOW FIELDS FROM Unknown error 1356