3.13. Collations
Collations are objects which allow specifying the sorting mode and character classification behavior either per column or operation. Collations can be used to override the way data is sorted in a database even if this one has its own mode defined by LC_COLLATE and LC_CTYPE attributes.
| Attribute | Description |
|---|---|
Collation | This field can be used to create a new object from an existing collation. |
Locale | This is a shortcut to specify the attributes LC_COLLATE and LC_CTYPE. |
Encoding | Charset in which the collation works. |
LC_COLLATE | Specify in which language the string sorting must be applied. |
LC_CTYPE | Specify in which language the character categorization (upper, lower and digit) must be applied. |
note
Note: the attributes Collation, Locale, LC_COLLATE and LC_CTYPE are mutually exclusive, thus you can't use all of them at once.
References
** Collation DDL **
https://www.postgresql.org/docs/current/static/sql-createcollation.html