----- Original Message -----
> From: "Zhangzhigang" <zzgang_2...@yahoo.com.cn>
> 
> Creating indexes after inserting massive data rows is faster than
> before inserting data rows.
> Please tell me why.

Plain and simple: the indices get updated after every insert statement, whereas 
if you only create the index *after* the inserts, the index gets created in a 
single operation, which is a lot more efficient.

I seem to recall that inside of a transaction (thus, InnoDB or so) the 
difference is markedly less; I might be wrong, though.


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