sql - Which of these approaches has better performance for large tables? -


Give two tables to A and B in a database schema. A and B are related to many relationships, many B. are present for each A, and B has a foreign key column a_id. Both tables have a primary key column id.

Which of the following two queries do better for large data sets in A and B? 

  from SELECT A. * A, B. WHERE AID = BAID

or 

  SELECT A From AID = BAIID

on an inner BB or are they equal?

All of these are equivalent to 4 major database system: Oracle , SQL Server , MySQL , PostgreSQL .

Join syntax (to be more accurate, using JOIN instead of STREIGHT_JOIN ) Applying the command will help MySQL .

See this answer for details:

This is generally considered to be more clean and JOIN < / Code> Readable to use syntax.

However, I use the Oracle code sample which normally uses the WHERE syntax.


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