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.
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Most SQL databases are like this. Except for the most basic addition, deletion, modification and query, most of the functions are different.
You may need ETL software
A more common one is kettle
http://community.pentaho.com/projects/data-integration/
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.