MySQL index on VARCHAR(1000) -


a varchar(1000) column included in where clause e.g. 

where propertyvalue in ('sample, ...')

the values unique not guaranteed/constrained be.

i want index , wondering best approach is. realise indexing column make inserts slower.

would storing hash of value char(64) , indexing , searching on faster? thinking fixed size value more suitable indexing.

i using 5.1 , innodb

the simplest approach use partial index:

create index on [...] propertyvalue(100) [...]

so long first 100 characters (in example) of columns reasonably distinctive, more sufficient make index work.


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