How to query different databases with one SQL statement
This time I will show you how to use a SQL statement to query different databases and one SQL statement to query different databases What are the precautions ? The following is a practical case, one Get up and take a look.
Requirements: A SQL statement queries related results from multiple databases and outputs them to the client
Investigation: springFrameworkcan configure multiple data sources; sql can also Multiple databases can be attached to one main database
Solution: Use the ATTACH DATABASE
statement to add multiple libraries to the main library to achieve the function
Syntax:
ATTACH DATABASE 'DatabaseName' As 'Alias-Name';
Example:
ATTACH DATABASE 'C:\Users\Administrator\Desktop\sqlite_data.sq3' As 'sd';
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website !
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