数据库 - 为什么MSSQL和MYSQL那么的不统一?
目前一个项目需要将愿数据库(sqlserver)中的数据取出并做一定处理后存入目标数据库(mysql),但是mssql和mysql无论是sql语句还是内置函数很多地方都不统一(比如mysql的自增是auto_increment,mssql的自增是identity(1,1)),数据传输和转换非常的不方便。同样是使用sql语句的关系型数据库，为什么要这么不统一呢？这是微软的锅吗？
目前一个项目需要将愿数据库(sqlserver)中的数据取出并做一定处理后存入目标数据库(mysql),但是mssql和mysql无论是sql语句还是内置函数很多地方都不统一(比如mysql的自增是auto_increment,mssql的自增是identity(1,1)),数据传输和转换非常的不方便。同样是使用sql语句的关系型数据库，为什么要这么不统一呢？这是微软的锅吗？
PHP中文网2017-04-17 14:20:33
Most SQL databases are like this. Except for the most basic addition, deletion, modification and query, most of the functions are different.
伊谢尔伦2017-04-17 14:20:33
You may need ETL software
A more common one is kettle
http://community.pentaho.com/projects/data-integration/
伊谢尔伦2017-04-17 14:20:33
Because standardization takes a long time, the SQL standard is only a subset of the functions that everyone supports, and each company has its own extensions. Some functions that everyone supports have not yet entered the standard, so each company has its own syntax. Oracle also has a lot of its own syntax.
Off-topic: I think Ti Zhu is really impetuous and likes to follow the crowd. This mentality is not conducive to learning new knowledge. If I don't understand or can't handle something, I feel that it must be someone else's fault. When I look at Microsoft, I think, oh, it must be Microsoft's fault. I really don't know where this victim mentality comes from. When SQL Server was developed, MySQL did not exist yet.
