Cannot set a row with mismatched columns

When setting up a table in a database, each row should have the same number of columns. However, if you encounter the error “cannot set a row with mismatched columns,” it means that you are trying to insert a row with a different number of columns than what is defined for the table.

To understand it better, let’s consider an example:

    CREATE TABLE employees (
      id INT,
      name VARCHAR(50),
      salary DECIMAL(10, 2)
    );
    
    INSERT INTO employees (id, name, salary) VALUES (1, 'John Doe', 5000.00);
    INSERT INTO employees (id, salary) VALUES (2, 4000.00); -- Incorrect statement
  

In the example above, we defined a table named “employees” with three columns: “id”, “name,” and “salary.” The first INSERT statement successfully inserts a row with all three columns specified.

However, the second INSERT statement tries to insert a row with only two columns specified: “id” and “salary.” This will result in the “cannot set a row with mismatched columns” error because it doesn’t match the number of columns defined for the table.

To fix this error, you need to ensure that the number of columns specified in the INSERT statement matches the number of columns defined for the table. In our example, we can fix the error by providing a value for the missing “name” column.

    INSERT INTO employees (id, name, salary) VALUES (2, 'Jane Smith', 4000.00); -- Correct statement
  

Now the second INSERT statement includes all three columns specified, and it will not throw the “cannot set a row with mismatched columns” error.