## 2.6.3
* Added new function `migrateEnableExtension`, to enable Postgres extensions in migrations.
## 2.6.2.2
* Because `text` and `varchar` are synonyms in Postgresql, don't attempt to migrate between them. [#762](https://github.com/yesodweb/persistent/pull/762)
## 2.6.2.1
* Fix bug where, if a custom column width was set, the field would be migrated every time [#742](https://github.com/yesodweb/persistent/pull/742)
## 2.6.2
* Expose new functions: `withPostgresqlPoolWithVersion`, `withPostgresqlConnWithVersion` and `createPostgresqlPoolModifiedWithVersion`.
## 2.6.1
* Match changes in persistent
* Clean up warnings
## 2.6
* Atomic upsert support for postgreSQL backend
## 2.5
* changes for read/write typeclass split
## 2.2.2
* Postgresql primary key is Int4, not Int8 [#519](https://github.com/yesodweb/persistent/issues/519)
## 2.2.1.2
* Allow postgresql-simple 0.5
## 2.2.1.1
Query pg_catalog instead of information_schema for metadata.
This helps with permission issues as reported in issue #501
## 2.2.1
* Fix treatment of `NULL`s inside arrays. For example, now you
can use `array_agg` on a nullable column.
* New derived instances for `PostgresConf`: `Read`, `Data` and `Typeable`.
* New `mockMigration` function. Works like `printMigration` but
doesn't need a database connection.
* Fix typo on error message of the `FromJSON` instance of `PostgresConf`.
## 2.2
* Optimize the `insertMany` function to insert all rows and retrieve their keys in one SQL query. [#407](https://github.com/yesodweb/persistent/pull/407)
## 2.1.6
* Postgresql exceptions [#353](https://github.com/yesodweb/persistent/issues/353)
## 2.1.5.3
Migrations for custom primary keys
## 2.1.5.2
Support foreign key references to composite primary keys #389
## 2.1.5
* Allow timestamp value in database to be serialized (presumes UTC timezone) [Yesod #391](https://github.com/yesodweb/persistent/issues/391)
## 2.1.4
* Treat unknown extension types as PersistDbSpecific values [#385](https://github.com/yesodweb/persistent/pull/385)
## 2.1.3
* Added a `Show` instance for `PostgresConf`.
* `createPostgresqlPoolModified` added, see [relevant mailing list discussion](https://groups.google.com/d/msg/yesodweb/qUXrEN_swEo/O0pFwqwQIdcJ)
## 2.1.2.1
Documentation typo fix
## 2.1.1
Added `FromJSON` instance for `PostgresConf`.