utf-8 vs latin1

Question

What are the advantages/disadvantages between using utf8 as a charset against using latin1?

If utf can support more chars and is used consistently wouldn't it always be the better choice? Is there any reason to choose latin1?

Answer 1

UTF8 Advantages:

1. Supports most languages, including RTL languages such as Hebrew.

2. No translation needed when importing/exporting data to UTF8 aware components (JavaScript, Java, etc).

UTF8 Disadvantages:

1. Non-ASCII characters will take more time to encode and decode, due to their more complex encoding scheme.

2. Non-ASCII characters will take more space as they may be stored using more than 1 byte (characters not in the first 127 characters of the ASCII characters set). A CHAR(10) or VARCHAR(10) field may need up to 30 bytes to store some UTF8 characters.

3. Collations other than utf8_bin will be slower as the sort order will not directly map to the character encoding order), and will require translation in some stored procedures (as variables default to utf8_general_ci collation).

4. If you need to JOIN UTF8 and non-UTF8 fields, MySQL will impose a SEVERE performance hit. What would be sub-second queries could potentially take minutes if the fields joined are different character sets/collations.

Bottom line:

If you don't need to support non-Latin1 languages, want to achieve maximum performance, or already have tables using latin1, choose latin1.

Otherwise, choose UTF8.