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1. Postgresql insert statement psychopg2 how to#
2. Postgresql insert statement psychopg2 serial#
3. Postgresql insert statement psychopg2 code#

Use PostgreSQL INSERT statement to insert data into a table.To get the last insert id from inserted row, you use the RETURNING clause of the INSERTstatement.įor example, the following statement inserts a new row into the links table and returns the last insert id: INSERT INTO links ( url, name) Output: INSERT 0 1 4) PostgreSQL INSERT- Getting the last insert id

Postgresql insert statement psychopg2 code#

VALUES( '', 'Google', '') Code language: SQL (Structured Query Language) ( sql ) The following statement inserts a new row with a specified date into the links table: INSERT INTO links ( url, name, last_update) To insert a date value into a column with the DATE type, you use the date in the format 'YYYY-MM-DD'. The following statement verifies the insert: 3) PostgreSQL INSERT – Inserting a date value VALUES( '', 'O''Reilly Media') Code language: SQL (Structured Query Language) ( sql ) For example: INSERT INTO links ( url, name) If you want to insert a string that contains a single quote ( ') such as O'Reilly Media, you have to use an additional single quote ( ') to escape it. The following SELECT statement shows the contents of the links table: SELECT * FROM links Code language: SQL (Structured Query Language) ( sql ) 2) PostgreSQL INSERT – Inserting character string that contains a single quote

Postgresql insert statement psychopg2 serial#

PostgreSQL automatically generates a sequential number for the serial column so you do not have to supply a value for the serial column in the INSERT statement. Therefore, PostgreSQL uses NULL to insert into the description column. In this example, the description is an optional column because it doesn’t have a NOT NULL constraint. In case you omit an optional column, PostgreSQL will use the column default value for insert. If you omit required columns in the INSERT statement, PostgreSQL will issue an error. To insert character data, you enclose it in single quotes (‘) for example 'PostgreSQL Tutorial'. The statement returns the following output: INSERT 0 1 Code language: Shell Session ( shell ) VALUES( '', 'PostgreSQL Tutorial') Code language: SQL (Structured Query Language) ( sql ) The following statement inserts a new row into the links table: INSERT INTO links ( url, name) 1) PostgreSQL INSERT – Inserting a single row into a table In this tutorial, you just need to execute it to create a new table.

Postgresql insert statement psychopg2 how to#

Note that you will learn how to create a new table in the subsequent tutorial. ) Code language: SQL (Structured Query Language) ( sql ) The following statement creates a new table called linksfor the demonstration: DROP TABLE IF EXISTS links RETURNING output_expression AS output_name Code language: SQL (Structured Query Language) ( sql ) PostgreSQL INSERT statement examples For example: INSERT INTO table_name(column1, column2, …) To rename the returned value, you use the AS keyword followed by the name of the output.

RETURNING id Code language: SQL (Structured Query Language) ( sql ) If you want to return just some information of the inserted row, you can specify one or more columns after the RETURNING clause.įor example, the following statement returns the id of the inserted row: INSERT INTO table_name(column1, column2, …) RETURNING * Code language: SQL (Structured Query Language) ( sql ) If you want to return the entire inserted row, you use an asterisk ( *) after the RETURNING keyword: INSERT INTO table_name(column1, column2, …) The INSERT statement also has an optional RETURNING clause that returns the information of the inserted row. The count is the number of rows that the INSERT statement inserted successfully. Typically, the INSERT statement returns OID with value 0.

PostgreSQL used the OID internally as a primary key for its system tables. The INSERT statement returns a command tag with the following form: INSERT oid count The columns and values in the column and value lists must be in the same order.