SQL varchar character limit
http://dev.mysql.com/doc/refman/5.0/en/char.html
The length can be specified as a value from 0 to 255 before MySQL 5.0.3,
and 0 to 65,535 in 5.0.3 and later versions.
I don't think your second paste is talking about MySQL.
EasyBB
I am a self learning developer/designer. I've been writing HTML since 2000 and still up to with the specifics of HTML5! CSS is another great coding language of mine, loving the CSS3 3D transforms and everything about it! I first started learning jQuery in 2012 and well that was a big mistake, so now I write everything in Vanilla JavaScript, it renders quicker and is a lot faster than going through a library.
Updated on May 24, 2020Comments
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EasyBB almost 4 years
I have read different explanations of
varchar
and so far I've gotten this:CHAR( ) fixed from 0 to 255 characters long VARCHAR( ) variable from 0 to 255 characters long TINYTEXT maximum length of 255 characters TEXT maximum length of 65535 characters BLOB maximum length of 65535 characters MEDIUMTEXT maximum length of 16777215 characters MEDIUMBLOB maximum length of 16777215 characters LONGTEXT maximum length of 4294967295 characters LONGBLOB maximum length of 4294967295 characters
and then this
char(n) variables store fixed-length character strings conisisting of exactly n characters (and, therefore, n bytes). They are limited to 8,000 characters in size.
nchar(n) variables store fixed-length Unicode character strings conisisting of exactly n characters (and, therefore, 2*n bytes). They are limited to 4,000 characters in size.
varchar(n) variables store non-fixed length character strings consisting of approximately n characters. They consume l+2 bytes of space, where l is the actual length of the string. They are limited to 8,000 characters in size.
- nvarchar(n) variables store non-fixed length Unicode character strings consisting of approximately n characters. They consume 2*l+2 bytes of space, where l is the actual length of the string. They are limited to 4,000 characters in size.
- varchar(max) variables store non-fixed length character strings consisting of up to 1,073,741,824 characters. They consume l+2 bytes of space, where l is the actual length of the string.
- nvarchar(max) variables store non-fixed length Unicode character strings consisting of up to 536,870,912 characters. They consume l*2+2 bytes of space, where l is the actual length of the string.
- text and ntext variables store up to 2GB of text data (ANSI and Unicode, respectively), but can not be used in many text operations. Therefore, they are usually only used to support legacy applications and have been replaced by the varchar(max) and nvarchar(max) data types.
So really what is the character max on
varchar
? Reason I am wondering is I am starting a simple littleCMS
and I don't want my SQL DB to overloaded with weight and as you can see for examplenvarchar(max)[length] * 2 + 2 nvarchar being 100,000 * 2 + 2 = 200,002 bytes (what is + 2 is it literal?)
Also I've read that
varchar(8,000)
is better thanvarchar(max)
so what would you suggest the type that I use for a variably changing character length, especially for content.