Re: Best Index Strategy

[Rick James]

> telephone LIKE '%7600639533%'

If possible, change that to

soas.telephone = '7600639533'
so that you _could_ index that column.

In that case, INDEX(address_type, telephone) would be beneficial.

Don't blindly use VARCHAR(255). Use reasonable, but conservative, lengths.

> `cc_exp_year` varchar(255) DEFAULT NULL COMMENT 'Cc Exp Year',

Is that a "year"? There is a datatype YEAR.

Are you storing Credit card info? I really, really, hope your security is very, very, tight.

> `cc_type` varchar(255) DEFAULT NULL COMMENT 'Cc Type',

Consider ENUM.

> `cc_last4` varchar(255) DEFAULT NULL COMMENT 'Cc Last4',

4 is a lot less than 255.

> KEY `IDX_SALES_FLAT_ORDER_GRID_STATUS` (`status`),

Low cardinality fields are rarely useful to index.