TRY…CATCH语句

shark实现了一种与异常处理的类似的错误处理机制，当TRY控制块内的SQL语句出现错误时，会继续执行CATCH控制块内的语句。

注意事项

• 本章节只包含shark新增的语法。

语法格式

• BEGIN TRY { sql_statement | statement_block } END TRY BEGIN CATCH [ { sql_statement | statement_block } ] END CATCH [ ; ]

参数说明

• sql_statement

  除事务管理语句外的任意SQL语句。

• statement_block

  除事务管理语句外的任意SQL语句块。

示例

opengauss=# create table test_3(a int);
opengauss=# begin try;
opengauss=# insert into test_3 values(2);
opengauss=# select 1/0;
ERROR:  division by zero
opengauss=# end try begin catch;
opengauss=# insert into test_3 values(3);
opengauss=# select 1/0;
ERROR:  division by zero
opengauss=# select * from test_3;
ERROR:  current catch block is failed, commands ignored until end of catch block
opengauss=# end catch;
opengauss=# select * from test_3;
 a
---
(0 rows)