Finding Maximum Count in MySQL
When attempting to find the maximum count of records in a MySQL table using the max(count(*)) aggregation function grouped by a specific column, you may encounter the error: "Invalid use of group function." This error occurs because the count(*) function is an aggregate function that cannot be used within another aggregate function like max.
To resolve this issue and obtain the maximum count of records grouped by a particular column, you can use the following alternative approach:
<code class="sql">SELECT name, COUNT(*) AS count_of_name FROM table_name GROUP BY name ORDER BY count_of_name DESC LIMIT 1</code>
In this query:
- name is the column you want to group the results by.
- COUNT(*) counts the number of rows in each group and aliases the result as count_of_name.
- GROUP BY name groups the results by the name column.
- ORDER BY count_of_name DESC orders the results in descending order of count_of_name.
- LIMIT 1 retrieves only the first row, which represents the group with the maximum count.
The above is the detailed content of How to Find the Maximum Count in MySQL Grouped by a Column?. For more information, please follow other related articles on the PHP Chinese website!

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