a76889b319
1. Avoid print large string in error log
If user load a unqualified large string, the all string will be saved in error log,
so the error log is too big that can not be shown be using `show load warnings on "url"`.
Err: `Got packet bigger than 'max_allowed_packet' bytes`
2. Remove duplicate help doc
Do not allow doc with same title, or error thrown when starting FE:
`java.lang.IllegalArgumentException: Multiple entries with same key:`
1.2 KiB
1.2 KiB
title, language
| title | language |
|---|---|
| coalesce | zh-CN |
coalesce
description
Syntax
coalesce(expr1, expr2, ...., expr_n))
返回参数中的第一个非空表达式（从左向右）
example
mysql> select coalesce(NULL, '1111', '0000');
+--------------------------------+
| coalesce(NULL, '1111', '0000') |
+--------------------------------+
| 1111 |
+--------------------------------+
keyword
COALESCE