To generate serial number i.e. row count in MySQL query, use the following syntax.
SELECT @yourVariableName − = @yourVariableName+1 anyAliasName, yourColumnName1,yourColumnName2,yourColumnName3,....N from yourTableName , (select @yourVariableName − = 0) as yourVariableName;
To understand the above syntax, let us create a table. The query to create a table is as follows −
mysql> create table tblStudentInformation -> ( -> StudentName varchar(20), -> StudentAge int, -> StudentMathMarks int -> ); Query OK, 0 rows affected (0.68 sec)
Insert some records in the table using insert command. The query is as follows −
mysql> insert into tblStudentInformation values('Carol',23,89);
Query OK, 1 row affected (0.18 sec)
mysql> insert into tblStudentInformation values('Bob',25,92);
Query OK, 1 row affected (0.22 sec)
mysql> insert into tblStudentInformation values('John',21,82);
Query OK, 1 row affected (0.15 sec)
mysql> insert into tblStudentInformation values('David',26,98);
Query OK, 1 row affected (0.21 sec)Display all records from the table using select statement. The query is as follows −
mysql> select *from tblStudentInformation;
The following is the output.
+-------------+------------+------------------+ | StudentName | StudentAge | StudentMathMarks | +-------------+------------+------------------+ | Carol | 23 | 89 | | Bob | 25 | 92 | | John | 21 | 82 | | David | 26 | 98 | +-------------+------------+------------------+ 4 rows in set (0.00 sec)
The following is the query to generate the serial number in MySQL query −
mysql> SELECT @serialNumber − = @serialNumber+1 yourSerialNumber, -> StudentName,StudentAge,StudentMathMarks from tblStudentInformation, -> (select @serialNumber − = 0) as serialNumber;
Here is the output displaying the row number in the form of serial number.
+------------------+-------------+------------+------------------+ | yourSerialNumber | StudentName | StudentAge | StudentMathMarks | +------------------+-------------+------------+------------------+ | 1 | Carol | 23 | 89 | | 2 | Bob | 25 | 92 | | 3 | John | 21 | 82 | | 4 | David | 26 | 98 | +------------------+-------------+------------+------------------+ 4 rows in set (0.00 sec)