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

1. opengauss=# create table test_3(a int);
2. opengauss=# begin try;
3. opengauss=# insert into test_3 values(2);
4. opengauss=# select 1/0;
5. ERROR:  division by zero
6. opengauss=# end try begin catch;
7. opengauss=# insert into test_3 values(3);
8. opengauss=# select 1/0;
9. ERROR:  division by zero
10. opengauss=# select * from test_3;
11. ERROR:  current catch block is failed, commands ignored until end of catch block
12. opengauss=# end catch;
13. opengauss=# select * from test_3;
14. a
15. ---
16. (0 rows)