Which MySQL datatype is more space efficient for scalable apps? TEXT or VARCHAR? -

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i'm building highly scalable app, , need know data type use small strings (50-1000 chars). heard varchar fixed sized , therefore might faster, text, chars might stored in seperate clob, , pointer in row data. smaller, have significant performance hit?

values in varchar columns variable-length strings. length can specified value 0 255 before mysql 5.0.3, , 0 65,535 in 5.0.3 , later versions.

if have mysql 5.0.3 or later, , don't need more 65k characters, doesn't matter 1 use, because both text , varchar have variable size in storage. if have many texts less 255 characters, can save 1 byte choosing varchar.

but on different aspect, choose data type more appropriate it. if store text, semantically text can exceed "standard" sizes easily, should use text datatype.


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