php - Does VARCHAR size limit matter? -


possible duplicate:
importance of varchar length in mysql table

when using varchar (assuming correct data type short string) size matter? if set 20 characters, take less space or faster 255 characters?

in general, varchar field, amount of data stored in each field determines footprint on disk rather maximum size (unlike char field has same footprint).

there upper limit on total data stored within fields of index of 900 bytes (900 byte index size limit in character length).

the larger make field, more people try use purposes other intended - , greater screen real-estate required show value - practice try pick right size, rather assuming if make large possible save having revisit design.


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