In the process of PHP development, sometimes we will encounter the following warning message:
PHP Warning: mysqli_query() expects parameter
This kind of warning message is generally related to MySQL query operations It's related. If we accidentally fill in the wrong parameters when using the mysqli_query() function, this warning message will appear. So how to deal with it? Here are some solutions for you.
Solution 1: Check the SQL statement
This kind of warning message usually appears when calling the mysqli_query() function. We need to first check whether the SQL statement passed to the function is correct, including whether the syntax is correct. , whether the query table name is correct, whether the condition logic is reasonable, etc. Generally speaking, we can test the SQL statement in the MySQL client first to ensure that the statement is executed correctly and then copy it to the PHP script.
Solution 2: Check whether the connection is normal
When a warning message appears, we also need to check whether the connection to the MySQL server is normal. For example, we can use the mysqli_connect() function to view the connection status and check whether the connection parameters are filled in correctly, including the MySQL server address, user name and password, etc.
Solution 3: Check the mysqli_query() parameter list
One of the common reasons for this warning message is that the parameter list passed to the mysqli_query() function is incorrect, such as the wrong data table name, etc. For the correct parameter list, please refer to the MySQL documentation or other reliable reference materials. Make sure that the parameters are filled in correctly before calling the function.
Summary:
In PHP development, it is normal to encounter warning messages. Each warning message has its own reason, and the solutions are also targeted. For the mysqli_query() function warning information, you can roughly check whether the SQL statement is correct, whether the connection is normal, and whether the parameter list is wrong. I hope the solutions in this article are helpful to everyone.
The above is the detailed content of PHP Warning: mysqli_query() expects parameter solution. For more information, please follow other related articles on the PHP Chinese website!

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