Available in versions: Dev (3.19) | Latest (3.18) | 3.17 | 3.16 | 3.15 | 3.14 | 3.13 | 3.12 | 3.11 | 3.10 | 3.9

Unique constraints

Applies to ✅ Open Source Edition   ✅ Express Edition   ✅ Professional Edition   ✅ Enterprise Edition

A candidate key that is not ideal for a Primary key should still be declared UNIQUE to enforce uniqueness, as well as for query performance reasons. In jOOQ, this can be done with the following approaches:

// Create a new table with columns and unnamed constraints
create.createTable("table")
      .column("column1", INTEGER)
      .column("column2", INTEGER)
      .column("column3", INTEGER)
      .constraints(
          unique("column1"),
          unique("column2", "column3")
      )
      .execute();

// Create a new table with columns and named constraints (recommended if you want to alter the constraint)
create.createTable("table")
      .column("column1", INTEGER)
      .column("column2", INTEGER)
      .column("column3", INTEGER)
      .constraints(
          constraint("uk1").unique("column1"),
          constraint("uk2").unique("column2", "column3")
      )
      .execute();

Dialect support

This example using jOOQ:

createTable("table")
      .column("column1", INTEGER)
      .constraints(
          constraint("uk").unique("column1")
      )

Translates to the following dialect specific expressions:

-- ACCESS, DB2, FIREBIRD, HANA, TERADATA
CREATE TABLE table (
  column1 integer,
  CONSTRAINT uk UNIQUE (column1)
)

-- ASE, SYBASE
CREATE TABLE table (
  column1 int NULL,
  CONSTRAINT uk UNIQUE (column1)
)

-- AURORA_MYSQL, AURORA_POSTGRES, DERBY, DUCKDB, EXASOL, H2, HSQLDB, MARIADB, MEMSQL, MYSQL, POSTGRES, REDSHIFT, 
-- SQLSERVER, VERTICA, YUGABYTEDB
CREATE TABLE table (
  column1 int,
  CONSTRAINT uk UNIQUE (column1)
)

-- BIGQUERY
CREATE TABLE table (
  column1 int64
)

-- COCKROACHDB
CREATE TABLE table (
  column1 int4,
  CONSTRAINT uk UNIQUE (column1)
)

-- INFORMIX
CREATE TABLE table (
  column1 integer,
  UNIQUE (column1) CONSTRAINT uk
)

-- ORACLE, SNOWFLAKE
CREATE TABLE table (
  column1 number(10),
  CONSTRAINT uk UNIQUE (column1)
)

-- SQLDATAWAREHOUSE
CREATE TABLE table (
  column1 int,
  CONSTRAINT uk UNIQUE (column1) NOT ENFORCED
)

-- SQLITE
CREATE TABLE "table" (
  column1 int,
  CONSTRAINT uk UNIQUE (column1)
)

-- TRINO
CREATE TABLE table (
  column1 int
)

(These are currently generated with jOOQ 3.19, see #10141), or translate your own on our website

Feedback

Do you have any feedback about this page? We'd love to hear it!

The jOOQ Logo