Try It SQLite GROUP BY with MAX, MIN, and AVG functions For example, to get total length and bytes for each album, you use the SUM function to calculate total milliseconds and bytes. You can use the SUM function to calculate total per group. Try It SQLite GROUP BY clause with SUM function example HAVING COUNT(trackid) > 15 Code language: SQL (Structured Query Language) ( sql ) For example, to get the albums that have more than 15 tracks, you use the following statement: SELECT To filter groups, you use the GROUP BY with HAVING clause. Try It SQLite GROUP BY with HAVING clause Tracks.albumid Code language: SQL (Structured Query Language) ( sql ) INNER JOIN albums ON albums.albumid = tracks.albumid You can query data from multiple tables using the INNER JOIN clause, then use the GROUP BY clause to group rows into a set of summary rows.įor example, the following statement joins the tracks table with the albums table to get the album’s titles and uses the GROUP BY clause with the COUNT function to get the number of tracks per album. Try It SQLite GROUP BY and INNER JOIN clause ORDER BY COUNT(trackid) DESC Code language: SQL (Structured Query Language) ( sql ) You can use the ORDER BY clause to sort the groups as follows: SELECT SELECTĪlbumid Code language: SQL (Structured Query Language) ( sql ) It uses the GROUP BY clause to groups tracks by album and applies the COUNT() function to each group. The following statement returns the album id and the number of tracks per album. SQLite GROUP BY clause with COUNT function We use the tracks table from the sample database for the demonstration. In case a statement contains a WHERE clause, the GROUP BY clause must come after the WHERE clause.įollowing the GROUP BY clause is a column or a list of comma-separated columns used to specify the group. The GROUP BY clause comes after the FROM clause of the SELECT statement. SELECTĬode language: SQL (Structured Query Language) ( sql ) The following statement illustrates the syntax of the SQLite GROUP BY clause. For each group, you can apply an aggregate function such as MIN, MAX, SUM, COUNT, or AVG to provide more information about each group. The GROUP BY clause returns one row for each group. The GROUP BY clause a selected group of rows into summary rows by values of one or more columns. The GROUP BY clause is an optional clause of the SELECT statement. Subquery can be used in conjunction with the DELETE statement like with any other statements mentioned above.įollowing example deletes records from COMPANY table for all the customers whose AGE is greater than or equal to 27.Summary: in this tutorial, you will learn how to use SQLite GROUP BY clause to make a set of summary rows from a set of rows. This would impact two rows and finally COMPANY table would have the following records − WHERE AGE IN (SELECT AGE FROM COMPANY_BKP Either single or multiple columns in a table can be updated when using a subquery with the UPDATE statement.Īssuming, we have COMPANY_BKP table available which is a backup of COMPANY table.įollowing example updates SALARY by 0.50 times in COMPANY table for all the customers, whose AGE is greater than or equal to 27. The subquery can be used in conjunction with the UPDATE statement. To copy the complete COMPANY table into COMPANY_BKP, following is the syntax − INSERT INTO table_name ) ]Ĭonsider a table COMPANY_BKP with similar structure as COMPANY table and can be created using the same CREATE TABLE using COMPANY_BKP as the table name. The selected data in the subquery can be modified with any of the character, date, or number functions.įollowing is the basic syntax is as follows − The INSERT statement uses the data returned from the subquery to insert into another table. Subqueries can also be used with INSERT statements. Subqueries can be used with the SELECT, INSERT, UPDATE, and DELETE statements along with the operators such as =,, >=, SELECT * A Subquery or Inner query or Nested query is a query within another SQLite query and embedded within the WHERE clause.Ī subquery is used to return data that will be used in the main query as a condition to further restrict the data to be retrieved.
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