You should also know about running the database server and running queries on that server.īelow is the SQL to create the schema and insert 17 quotes: CREATE TABLE quote ( ![]() It is expected that you know about relational databases and PostgreSQL. Example for Postgres Like #įor this guide on Postgres LIKE, you will use the example of Quotes from the Node.js PostgreSQL post. In the next section, you will learn about the Quotes example used in the Node.js PostgreSQL tutorial. You can also do something similar with a Regex like /J.*/gm as seen in this Regex 101 example. Now the above SELECT where will list out all the customers whose name starts with a J. In the above example, if you wanted to list all customers whose first name starts with a J then you can write it as: SELECT * from customer WHERE first_name LIKE ‘J % In case you want to filter out rows with a WHERE expression but based on some pattern in the string then you will use the LIKE expression. You can also use WHERE in the update and delete operation, as mentioned. If the table had 100K rows and 5 of the customers had their first name exactly as John those 5 rows would be selected. For instance, if you want to select all the rows in a table of customers with the first name John, it can be written as: SELECT * from customer WHERE first_name = ‘John’ The WHERE expression in relational databases including PostgreSQL is used to filter out rows while doing a select, update or delete operation. In this tutorial, you will learn how to use the LIKE expression in a WHERE statement to get rows that match or do not match a given pattern. ![]() ![]() It is an open-source RDBMS having 35 years of active development behind it. PostgreSQL is one of the most popular relational databases.
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