Count the number of occurrences of a string in a VARCHAR field in MySQL?

To count the number of occurrences of a string in a VARCHAR, we can use the logic of subtraction with length. First, we will create a table with the help of create command.

mysql> create table StringOccurrenceDemo
   -> (
   -> Cases varchar(100),
   -> StringValue varchar(500)
   -> );
Query OK, 0 rows affected (0.56 sec) 

After executing the above table, we will insert records into the table. The query is as follows −

mysql> insert into StringOccurrenceDemo values('First','This is MySQL Demo and MySQL is an open source RDBMS');
Query OK, 1 row affected (0.07 sec)

mysql> insert into StringOccurrenceDemo values('Second','There is no');
Query OK, 1 row affected (0.20 sec)

mysql> insert into StringOccurrenceDemo values('Third','There is MySQL,Hi MySQL,Hello MySQL');
Query OK, 1 row affected (0.17 sec)

Display all records with the help of select statement.

mysql> select *From StringOccurrenceDemo;

The following is the output.

+--------+------------------------------------------------------+
| Cases  | StringValue                                          |
+--------+------------------------------------------------------+
| First  | This is MySQL Demo and MySQL is an open source RDBMS |
| Second | There is no                                          |
| Third  | There is MySQL,Hi MySQL,Hello MySQL                  |
+--------+------------------------------------------------------+
3 rows in set (0.00 sec)

The following is the query to count the occurrences of string “MySQL”. The result will get displayed in the column ‘NumberOfOccurrenceOfMySQL’

mysql> SELECT Cases,StringValue,
   -> ROUND (
   -> (
   -> LENGTH(StringValue)- LENGTH( REPLACE (StringValue, "MySQL", "") )
   -> ) / LENGTH("MySQL")
   ->  ) AS NumberOfOccurrenceOfMySQL
   -> from StringOccurrenceDemo;

Here is the output.

+--------+------------------------------------------------------+---------------------------+
| Cases  | StringValue                                          |  NumberOfOccurrenceOfMySQL|
+--------+------------------------------------------------------+---------------------------+
| First  | This is MySQL Demo and MySQL is an open source RDBMS |                         2 |
| Second | There is                                             |                         0 |
| Third  | There is MySQL,Hi MySQL,Hello MySQL                  |                         3 |
+--------+------------------------------------------------------+---------------------------+
3 rows in set (0.05 sec)

The above output shows that we have found the count for occurrences of string ‘MySQL’.