https://www.postgresqltutorial.com › postgresql-tutorial › postgresql-primary-key
PostgreSQL Primary Key - PostgreSQL TutorialCONSTRAINT constraint_name PRIMARY KEY(column_1, column_2,...); PostgreSQL primary key examples. Let’s explore some examples of using the PostgreSQL primary key. 1) Creating a table with a primary key that consists of one column. The following statement creates a table with a primary key that consists of one column:
https://www.postgresqltutorial.com › postgresql-tutorial › postgresql-serial
Using PostgreSQL SERIAL to Create Auto-increment ColumnsIn this tutorial, you will learn how to use the PostgreSQL SERIAL to create an auto-increment column in a database table.
https://stackoverflow.com › questions › 2944499
How to add an auto-incrementing primary key to an existing table in ...Suppose you have a table table_name, to which you want to add an auto-incrementing, primary-key id (surrogate) column. The recommended way is using the form GENERATED { ALWAYS | BY DEFAULT } AS IDENTITY [ ( sequence_options ) ]. e.g. ALTER TABLE table_name ADD COLUMN id INTEGER PRIMARY KEY GENERATED ALWAYS AS IDENTITY; or
https://www.postgresql.org › docs › current › sql-altertable.htm
PostgreSQL: Documentation: 17: ALTER TABLETo add a column and fill it with a value different from the default to be used later: ALTER TABLE transactions ADD COLUMN status varchar(30) DEFAULT 'old', ALTER COLUMN status SET default 'current'; Existing rows will be filled with old, but then the default for subsequent commands will be current.
https://www.tutorialkart.com › postgresql › postgresql-make-column-primary-key
PostgreSQL - How to make an existing column as PRIMARY KEY? - Tutorial KartYou can make an existing column of PostgreSQL Table as PRIMARY KEY using ALTER TABLE query and adding a constraint.
https://www.beekeeperstudio.io › blog › postgres-add-pk-to-table
Adding a Primary Key to an Existing Table in PostgreSQLFor example, if you want to add a primary key to a table named customer that has columns named customer_id, first_name, and last_name, you could use the following ALTER TABLE command: ALTER TABLE customer ADD PRIMARY KEY ( customer_id );
https://www.postgresql.org › docs › current › sql-createtable.htm
PostgreSQL: Documentation: 17: CREATE TABLECreate a range partitioned table with multiple columns in the partition key: CREATE TABLE measurement_year_month ( logdate date not null, peaktemp int, unitsales int ) PARTITION BY RANGE (EXTRACT(YEAR FROM logdate), EXTRACT(MONTH FROM logdate)); Create a list partitioned table:
https://www.techonthenet.com › postgresql › primary_keys.php
PostgreSQL: Primary Keys - TechOnTheNetThe syntax to create a primary key using the CREATE TABLE statement in PostgreSQL is: CREATE TABLE table_name. ( column1 datatype [ NULL | NOT NULL ], column2 datatype [ NULL | NOT NULL ], ... CONSTRAINT constraint_name. PRIMARY KEY (index_col1, index_col2, ... index_col_n) ); OR. CREATE TABLE table_name. (
https://www.postgresql.org › docs › current › ddl-constraints.html
PostgreSQL: Documentation: 17: 5.5. ConstraintsCREATE TABLE example ( a integer, b integer, c integer, PRIMARY KEY (a, c)); Adding a primary key will automatically create a unique B-tree index on the column or group of columns listed in the primary key, and will force the column(s) to be marked NOT NULL. A table can have at most one primary key. (There can be any number of unique and not ...
https://www.postgresqltutorial.com › postgresql-tutorial › postgresql-add-column
PostgreSQL ADD COLUMN: Add One or More Columns to a TableThis tutorial shows you how to use the PostgreSQL ADD COLUMN statement to add one or more columns to an existing database table.
