Oracle SQL difference between varchar2(n) and varchar2(n char) -


scripts here @ work declare varchar2 columns varchar2(n char). not see difference , curious. thanks!

based on this resource

oracle9i , above allow varchar2 columns defined number of bytes varchar2(50 byte) or number of characters varchar2(50 char), the latter useful if database ever converted run double-byte character set (such japanese), won't have edit column sizes. default measure, byte, set nls_length_semantics.

if create column varchar2 (50) store 10 bytes, oracle save 10 bytes disc. not mean should create varchar2 (4000) columns 'just in case space needed', bad idea reduce performance , maintainability of application.


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