Am 12.02.2014 02:23, schrieb Zhigang Zhang:
> For example:
> Select * from T where col like ‘%abcd’;
> The table T is myisam table and we created a index on col.
> As we known, this like sql does not use the index created on col, it confuse
> me, why?
> I think in mysiam engine, the index data is smaller, it can use index link
> list to optimize it so as to reduce the disk scan than to the whole table
because ‘%abcd’ can't work in case of a index
how do you imagine that?
read how a index works technically
'abcd%' may work but '%abcd' is impossible
independent what engine, this don't work and won't ever work
you may have luck with fulltext search (and it's other drawbacks)
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