Solution to PHP Warning: mysql_fetch_array(): supplied argument is not

For some web developers, they may have encountered the error message "PHP Warning: mysql_fetch_array(): supplied argument is not" when writing programs in PHP. This error message may appear when performing an operation to obtain database table data, especially when using a MySql database.

The solution to this error message can include the following steps:

1. Check the database table

First, we need to confirm whether the database table exists , whether it is correctly linked to the program. If the corresponding database table does not exist, or the database link is not available, the data in the table cannot be obtained, resulting in this error message. The solution could be to check the MySql server settings, or debug the PHP code linked to the database.

2. Confirm whether the query SQL statement is correct

If the database table exists and the link is successful, but the error message still appears, you need to manually check the query SQL statement in the program is it right or not. When writing programs in PHP, we can use statements similar to "SELECT * FROM table WHERE condition" to obtain specified data in the database table. If the query statement is written incorrectly or the syntax is incorrect, this error message will also occur. The solution can be to check the query conditions, confirm the correctness of the query statement, etc.

3. Check the returned data type

After querying the data and obtaining the query results, we need to ensure that the returned data type is consistent with the data type in the program. MySQL provides a variety of return data types, such as associative array, indexed array, etc. If an incorrect data type is used in the program to obtain query results, this error message will also occur. The solution can be to confirm whether the data type used by the program is correct, or to check whether the return data type is consistent with the data type used in the program.

4. Check the validity of the result set

Finally, we also need to manually check the validity of the result set. Obtaining data results does not mean that the result set is necessarily valid. If an invalid SQL statement is used, or the conditions are insufficient to obtain any data, the query result will be an empty result set. In this case, using the mysql_fetch_array function to obtain data will also cause this error message to appear. The solution can be to confirm whether the SQL statements used by the program are correct, or to manually debug the program to find the problem.

In short, if you encounter the error message "PHP Warning: mysql_fetch_array(): supplied argument is not" when writing a program in PHP, you need to gradually investigate the cause of the error message and take corresponding solutions. method. These steps include confirming whether the database table exists, whether the query SQL statement is correct, checking the return data type and the validity of the result set, etc. Only through step-by-step troubleshooting through these methods can the problem be truly solved.

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