For this we will create a new table and discuss in detail. PART II: We will try to apply group by command more than one fields. $sql="SELECT count(*) as total_records, class FROM `student` group by class " Require "./config.php" // Database connection Here is a sample code to understand how to use group by query using PHP script and PDO. You can download the SQL dump of this stduent2_1 table with added duplicate data at the end of this page.īy using group by on a date field we can generate list on calendar year, financial year, month wise Sample code SELECT name, COUNT(id) AS no from student2_1 group by name having no > 1 We will create another table student2_1 by using same data and by adding some duplicate records. We can find out duplicate records in a table by using group by command. Sum(CASE WHEN gender ='Female' THEN 1 ELSE 0 END) as Female Sum(CASE WHEN gender ='male' THEN 1 ELSE 0 END) as Male, We can further break the gender column to get number of male and female in each class by using SQL case. Using two columns with GROUP BY SELECT class,gender, COUNT( * ) No FROM student In this tutorial, you have learned how to use the SQLite IN operator to match a value with a list of values or a subquery.GROUP BY with COUNT(), MIN(),MAX(),AVG() SELECT class, count(*) no, AVG(mark),MAX(mark),MIN(mark),SUM(mark)įROM student GROUP BY class ORDER BY no DESC class Genreid NOT IN ( 1, 2, 3) Code language: SQL (Structured Query Language) ( sql ) The following statement returns a list of tracks whose genre id is not in a list of (1,2,3). Then, the outer query return all tracks whose album id matches with the album id list returned by the subquery.First, the subquery returns a list of album ids that belong to the artist id 12.) Code language: SQL (Structured Query Language) ( sql ) To get the tracks that belong to the artist id 12, you can combine the IN operator with a subquery as follows: SELECT WHERE artistid = 12 Code language: SQL (Structured Query Language) ( sql ) The following query returns a list of album id of the artist id 12: SELECT albumid SQLite IN operator with a subquery example If you have a query that uses many OR operators, you can consider using the IN operator instead to make the query more readable. MediaTypeId = 1 OR MediaTypeId = 2 ORDER BY Name ASC Code language: SQL (Structured Query Language) ( sql )Īs you can see from the queries, using the IN operator is much shorter. This query uses the OR operator instead of the IN operator to return the same result set as the above query: SELECT ORDER BY Name ASC Code language: SQL (Structured Query Language) ( sql ) The following statement uses the IN operator to query the tracks whose media type id is 1 or 2. We will use the Tracks table from the sample database for the demonstration. To negate the list of values, you use the NOT IN operator. The IN operator returns true or false depending on whether the expression matches any value in a list of values or not. The returned type of expression and values in the list must be the same. The expression can be any valid expression or a column of a table.Ī list of values is a fixed value list or a result set of a single column returned by a subquery. The syntax of the IN operator is as follows: expression IN (value_list|subquery) Code language: SQL (Structured Query Language) ( sql ) The SQLite IN operator determines whether a value matches any value in a list or a subquery. As we mentioned earlier, an inner join will not include any rows where there is not a mutual match from both tables. Summary: in this tutorial, you will learn how to use the SQLite IN operator to determine whether a value matches any value in a list of values or a result of a subquery.
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