Mysql 自定义函数-下划线转驼峰

83 阅读 0 评论 55 点赞

我是靠谱客的博主强健大白，最近开发中收集的这篇文章主要介绍Mysql 自定义函数-下划线转驼峰，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

mysql没有直接处理的函数，需要先自定义一个函数运行函数：
CREATE FUNCTION underlineToCamel(paramString VARCHAR(200)) RETURNS varchar(200) CHARSET utf8
DETERMINISTIC
begin
set paramString = LOWER(paramString);
set paramString = replace(paramString, ‘_a’, ‘A’);
set paramString = replace(paramString, ‘_b’, ‘B’);
set paramString = replace(paramString, ‘_c’, ‘C’);
set paramString = replace(paramString, ‘_d’, ‘D’);
set paramString = replace(paramString, ‘_e’, ‘E’);
set paramString = replace(paramString, ‘_f’, ‘F’);
set paramString = replace(paramString, ‘_g’, ‘G’);
set paramString = replace(paramString, ‘_h’, ‘H’);
set paramString = replace(paramString, ‘_i’, ‘I’);
set paramString = replace(paramString, ‘_j’, ‘J’);
set paramString = replace(paramString, ‘_k’, ‘K’);
set paramString = replace(paramString, ‘_l’, ‘L’);
set paramString = replace(paramString, ‘_m’, ‘M’);
set paramString = replace(paramString, ‘_n’, ‘N’);
set paramString = replace(paramString, ‘_o’, ‘O’);
set paramString = replace(paramString, ‘_p’, ‘P’);
set paramString = replace(paramString, ‘_q’, ‘Q’);
set paramString = replace(paramString, ‘_r’, ‘R’);
set paramString = replace(paramString, ‘_s’, ‘S’);
set paramString = replace(paramString, ‘_t’, ‘T’);
set paramString = replace(paramString, ‘_u’, ‘U’);
set paramString = replace(paramString, ‘_v’, ‘V’);
set paramString = replace(paramString, ‘_w’, ‘W’);
set paramString = replace(paramString, ‘_x’, ‘X’);
set paramString = replace(paramString, ‘_y’, ‘Y’);
set paramString = replace(paramString, ‘z’, ‘Z’);
set paramString = replace(paramString, '’, ‘’);
RETURN paramString;
end

原文链接：https://blog.csdn.net/qq_43565104/article/details/108821559
创建一个函数以后可以直接把有下划线的列放入处理
删除函数命名： drop function underlineToCamel;
演示：select underlineToCamel(‘java_bean_obj’) from dual ;
输出结果：javaBeanObj

人懒所以写个工具后续再优化mybatis等等自动生成直接上代码上结果对比
SELECT
CONCAT(
columnComment,
annotations,
tableField,
data_type,
(select underlineToCamel(t.column_name))
) AS 实体类,
(select underlineToCamel(t.column_name)) as aaa,
t.*
from (
SELECT
CONCAT(’/**n * ‘,COLUMN_COMMENT,’n */n’) as columnComment,
CONCAT(’@Schema(description = “’,column_name,’”)n’) as annotations,
CONCAT(’@TableField("’,COLUMN_COMMENT,’")n’) as tableField,
COLUMN_COMMENT,
(
CASE
data_type
WHEN ‘varchar’
THEN ‘private String’
WHEN ‘bigint’
THEN ‘private Long’
WHEN ‘int’
THEN ‘private Integer’
WHEN ‘date’
THEN ‘private Date’
WHEN ‘text’
THEN ‘private String’
WHEN ‘datetime’
THEN ‘private java.sql.Timestamp’
ELSE ‘NULL’
END
) AS data_type,
CONCAT(’ ‘,LOWER(column_name),’;n’) as column_name
FROM
information_schema.columns
WHERE TABLE_NAME = ‘替换自己表名’ ) t