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CREATE COLLATION(7) | PostgreSQL 9.6.12 Documentation | CREATE COLLATION(7) |
NAME¶
CREATE_COLLATION - define a new collationSYNOPSIS¶
CREATE COLLATION name ( [ LOCALE = locale, ] [ LC_COLLATE = lc_collate, ] [ LC_CTYPE = lc_ctype ] ) CREATE COLLATION name FROM existing_collation
DESCRIPTION¶
CREATE COLLATION defines a new collation using the specified operating system locale settings, or by copying an existing collation.To be able to create a collation, you must have CREATE privilege on the destination schema.
PARAMETERS¶
nameThe name of the collation. The collation name can be
schema-qualified. If it is not, the collation is defined in the current
schema. The collation name must be unique within that schema. (The system
catalogs can contain collations with the same name for other encodings, but
these are ignored if the database encoding does not match.)
locale
This is a shortcut for setting LC_COLLATE and LC_CTYPE at
once. If you specify this, you cannot specify either of those
parameters.
lc_collate
Use the specified operating system locale for the
LC_COLLATE locale category. The locale must be applicable to the current
database encoding. (See CREATE DATABASE (CREATE_DATABASE(7)) for the
precise rules.)
lc_ctype
Use the specified operating system locale for the
LC_CTYPE locale category. The locale must be applicable to the current
database encoding. (See CREATE DATABASE (CREATE_DATABASE(7)) for the
precise rules.)
existing_collation
The name of an existing collation to copy. The new
collation will have the same properties as the existing one, but it will be an
independent object.
NOTES¶
Use DROP COLLATION to remove user-defined collations.See Section 23.2, “Collation Support”, in the documentation for more information about collation support in PostgreSQL.
EXAMPLES¶
To create a collation from the operating system locale fr_FR.utf8 (assuming the current database encoding is UTF8):CREATE COLLATION french (LOCALE = 'fr_FR.utf8');
To create a collation from an existing collation:
CREATE COLLATION german FROM "de_DE";
This can be convenient to be able to use operating-system-independent collation names in applications.
COMPATIBILITY¶
There is a CREATE COLLATION statement in the SQL standard, but it is limited to copying an existing collation. The syntax to create a new collation is a PostgreSQL extension.SEE ALSO¶
ALTER COLLATION (ALTER_COLLATION(7)), DROP COLLATION (DROP_COLLATION(7))2019 | PostgreSQL 9.6.12 |