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Find the Number of Columns in a MySQL Table
To find the number of columns in a MySQL table, use the count(*) function with information_schema.columns and the WHERE clause. Let us see an example.
Creating a table.
mysql> create table NumberOfColumns -> ( -> id int, -> FirstName varchar(100), -> LastName varchar(100), -> Age int, -> Address varchar(100) -> ); Query OK, 0 rows affected (0.70 sec)
Inserting records into table.
mysql> insert into NumberOfColumns values(1,'Shane','Watson',36,'Australia'); Query OK, 1 row affected (0.15 sec) mysql> insert into NumberOfColumns values(2,'Carol','Taylor',24,'US'); Query OK, 1 row affected (0.13 sec)
To display all records.
mysql> select *from NumberOfColumns;
Here is the output.
+------+-----------+----------+------+-----------+ | id | FirstName | LastName | Age | Address | +------+-----------+----------+------+-----------+ | 1 | Shane | Watson | 36 | Australia | | 2 | Carol | Taylor | 24 | US | +------+-----------+----------+------+-----------+ 2 rows in set (0.00 sec)
Now let us see the syntax to count the number of columns in a table.
SELECT count(*) AS anyName FROM information_schema.columns WHERE table_name =' yourTableName';
Applying the above syntax in the example table with the name ?NumberOfColumns'.
mysql> SELECT count(*) AS NUMBEROFCOLUMNS FROM information_schema.columns -> WHERE table_name ='NumberOfColumns';
Here is the output.
+-----------------+ | NUMBEROFCOLUMNS | +-----------------+ | 5 | +-----------------+ 1 row in set (0.00 sec)
The alternate query to find the number of columns.
SELECT COUNT(*) AS anyName FROM INFORMATION_SCHEMA.COLUMNS WHERE table_schema = 'yourDatabaseName' AND table_name = 'yourTableName';
Applying the second query to a database which has the name ?business'.
mysql> SELECT COUNT(*) AS NUMBEROFCOLUMNS FROM INFORMATION_SCHEMA.COLUMNS -> WHERE table_schema = 'business' AND table_name = 'NumberOfColumns';
The output displays the number of columns.
+-----------------+ | NUMBEROFCOLUMNS | +-----------------+ | 5 | +-----------------+ 1 row in set (0.00 sec)
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