PostgreSQL Database
Published 15 February 2024
PostgreSQL
- Verified Versions: 9.2, 17
- Maintainer: Redgate
Supported Versions and Support Levels
- For information regarding the supported version and support levels available, please see Supported Databases for Flyway
- For information regarding the Flyway features available, please see Flyway feature summary
Driver
Item | Details |
---|---|
URL format | jdbc:postgresql://host:port/database |
SSL support | Yes - add ?ssl=true |
Ships with Flyway Command-line | Yes |
Maven Central coordinates | org.postgresql:postgresql |
Supported versions | 9.3-1104-jdbc4 and later |
Default Java class | org.postgresql.Driver |
Java Usage
PostgreSQL support is a separate dependency for Flyway and will need to be added to your Java project to access these features.
PostgreSQL is found within the flyway-database-postgresql
plugin module.
Maven
Redgate
<dependency>
<groupId>com.redgate.flyway</groupId>
<artifactId>flyway-database-postgresql</artifactId>
</dependency>
Open Source
<dependency>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-database-postgresql</artifactId>
</dependency>
Gradle
Redgate
dependencies {
implementation "com.redgate.flyway:flyway-database-postgresql"
}
Open Source
dependencies {
implementation "org.flywaydb:flyway-database-postgresql"
}
SQL Script Syntax
- Standard SQL syntax with statement delimiter ;
- Stored procedures (
CREATE FUNCTION
with$$
escapes, as generated by pg_dump) COPY ... FROM STDIN
(as generated by pg_dump)
Compatibility
- DDL exported by pg_dump can be used unchanged in a Flyway migration.
- Any PostgreSQL sql script executed by Flyway, can be executed by the PostgreSQL command-line tool and other PostgreSQL-compatible tools (after the placeholders have been replaced).
Example
/* Single line comment */ CREATE TABLE test_data ( value VARCHAR(25) NOT NULL PRIMARY KEY ); /* Multi-line comment */ -- Multi-statement PostgreSQL function CREATE FUNCTION AddData() RETURNS INTEGER AS $$ BEGIN INSERT INTO test_data (value) VALUES ('Hello'); RETURN 1; END; $$ LANGUAGE plpgsql; SELECT * INTO TEMP adddata_temp_table FROM AddData() ; -- Single-statement PostgreSQL function CREATE FUNCTION add(integer, integer) RETURNS integer LANGUAGE sql IMMUTABLE STRICT AS $_$select $1 + $2;$_$; -- Placeholder INSERT INTO ${tableName} (name) VALUES ('Mr. T');
Authentication
Flyway supports the following PostgreSQL authentication methods:
- URL authentication
- SCRAM
- pgpass
URL authentication
The user and password can be provided in the JDBC URL, in the form
jdbc:postgresql://<host>:<port>/<database>?user=myUsername&password=myPassword&<key1>=<value1>&<key2>=<value2>...
In this case, they do not need to be passed separately in configuration and the Flyway commandline will not prompt for them.
SCRAM
SCRAM authentication encryption is supported transparently using the current driver (42.2.14) - note that
.jre6
and .jre7
versions of the driver for older JREs do not support it.
pgpass
Authentication can be done with a pgpass file to retrieve the password for a connection, in which case it does not need to be supplied in configuration. If the path to a pgpass file is set in the environment variable PGPASSFILE
, it will be read from here. If not, then in Windows the file will be read from the location %APPDATA%\postgresql\pgpass.conf
, otherwise it is read from~/.pgpass
. You can read more about pgpass files and their structure here.
Lock Types
By default Flyway uses a transactional lock with PostgreSQL, however this can cause issues with certain SQL statements, most notably CREATE INDEX CONCURRENTLY
. In this scenario, transactional locks can be replaced with session-level locks by setting flyway.postgresql.transactional.lock=false
in your configuration.
Limitations
- No support for psql meta-commands with no JDBC equivalent like
\set
- Clean does not remove objects created by extensions. It is therefore highly recommended to create your extensions
using
CREATE EXTENSION IF NOT EXISTS
in order to be able to clean and (re-)migrate your schemas at will - No support for cleaning referenced large objects in
pg_largeobject
(Issue 1934) - No support for the
passfile
orhostaddr
parameter when using pgpass as there is no JDBC equivalent
Feature support for check command
Support for the check command on PostgreSQL databases is currently ongoing. Basic support for the following object types has been implemented.
- Aggregates
- Domains
- Enums
- Foreign Keys
- Functions
- Indexes
- Materialized Views
- Procedures
- Schemas
- Sequences
- Tables
- Triggers
- Views