Here the ONLY keyword indicates that the query should apply only to cities, and not any tables below cities in the inheritance hierarchy. On the other hand, the following query finds all the cities that are not state capitals and are situated at an elevation over 500 feet: Given the sample data from the PostgreSQL tutorial (see Section 2.1), this returns: ![]() For example, the following query finds the names of all cities, including state capitals, that are located at an elevation over 500 feet: In PostgreSQL, a table can inherit from zero or more other tables, and a query can reference either all rows of a table or all rows of a table plus all of its descendant tables. State capitals also have an extra column, state, that shows their state. In this case, the capitals table inherits all the columns of its parent table, cities. We define the capitals table so that it inherits from cities: However, what happens when we want to ask for data about a city, regardless of whether it is a capital or not? The inheritance feature can help to resolve this problem. This can be done by creating two tables, one for state capitals and one for cities that are not capitals. We want to be able to quickly retrieve the capital city for any particular state. Each state has many cities, but only one capital. ![]() Let's start with an example: suppose we are trying to build a data model for cities. (SQL:1999 and later define a type inheritance feature, which differs in many respects from the features described here.) This write-up shows how to insert multiple rows into a Postgres table with the help of several examples.PostgreSQL implements table inheritance, which can be a useful tool for database designers. PostgreSQL provides a returning clause that can be used with the INSERT query that returns the currently inserted rows. Finally, specify a VALUES keyword followed by the list of values to be inserted in multiple rows. Next, specify a column or list of columns in the parentheses. To do that, use the INSERT INTO query followed by the table name into which you want to insert the rows. To insert multiple rows in a table, the comma-separated syntax is used. The output verified that the ORDER BY clause sorted the rows in ascending order (based on article_id). Let’s run the following command to sort the rows in ascending order: SELECT * FROM article_details However, the ORDER BY clause can be used to sort the table’s data in a specific order. PostgreSQL maintains the insertion order. Let’s execute the below command to see the updated table: SELECT * FROM article_details The output shows that the RETURNING clause returns the newly inserted rows. Postgres provides an optional clause named RETURNING that can be used with the INSERT statement to return the currently inserted data: INSERT INTO The output clarifies that five rows have been inserted into the targeted table successfully.Įxample #2: How to Insert and Return Multiple Rows in PostgreSQL? You can check/verify the inserted data by executing the below-given query: SElECT * FROM article_details ![]() Let’s run the INSERT INTO statement to insert five new rows to the selected table: INSERT INTOĪrticle_details(article_id, article_title, published_date) The output shows that the article_details table has three columns: article_id, article_title, and published_date. We have already created a table named article_details whose details are as follows: SELECT * FROM article_details Finally, specify a VALUES keyword followed by the list of values to be inserted in multiple rows.Įxample #1: How to Insert Multiple Rows to a Table in PostgreSQL?.Next, specify a column or list of columns in the parentheses. ![]()
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