char
, varchar
, nchar
, nvarchar
are actually strings
the size
helps to determine how long the string is...
by the way
char
has a fixed length, so if you want to have "1"
in a char(2)
the contents will be actual "1 "
varchar(2)
will be "1"
the n
part stands for unicode, so everything inside those fields will be in Unicode.
normally we use nvarchar
to save some space on the data, as if you have a char(250)
the database will always save the full length, as an empty varchar(250)
will be nothing.
In our programming language we then use padding to do what char
does, for example, in C#
"1".PadLeft(2);
"1".PadRight(2);
will output " 1"
and "1 "
respectively.
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