Unknown column in 'field list' error on MySQL Update query

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byAlex Kataev·Dec 25, 2024

The error indicates a non-existent column name in your UPDATE query. Confirm the correctness of the column and table names, watching out for spelling and case. Consider fixing your query as such:

Wrong:

UPDATE table SET does_not_exist = 'new_value';

Right:

UPDATE table SET correct_col = 'new_value' WHERE id = 123;

Replace does_not_exist with the correct column name from table, and id with a valid identifier.

Mastering MySQL quoting styles

In MySQL, backticks should only encompass column names and table identifiers. Conversely, string values must be enveloped in single quotes ' ' or double quotes " ". Here's what the correct syntax looks like:

UPDATE `table` SET `column_name` = 'desired_value' WHERE `id` = 'identifier';

Notice the use of backticks around table and column names, while the string and identifier values are surrounded by single quotes.

Verifying column existence

Before an UPDATE, ensure the column indeed exists in the table. This can be done by viewing the schema or using the DESCRIBE command. Any discrepancy in column names, including trailing white spaces, could trigger an error #1054.

The art of Joining

If your update relies on information from another table, use an INNER JOIN and reference columns accurately. Aliases can be a lifesaver to avoid ambiguity:

-- 'u' and 't', best buddies in our query world!
UPDATE u
SET u.fellow = 'y'
FROM MASTER_USER_PROFILE AS u
INNER JOIN TRAN_USER_BRANCH AS t
ON u.USER_ID = t.USER_ID
WHERE t.BRANCH_ID = 17;

Dealing with Nested queries and triggers

Sometimes you are dealing with a condition living in a different table or a meddling trigger interfering with the update. In complex predicaments, a nested query may come in handy. Always be watchful of triggers that might alter your updates and test your queries with simpler conditions to isolate the problem.

Trimming spaces and playing nice with aliases

Even an unintended space in a column name can lead to the unknown column error. Trim those spaces, friends! Use aliases for easier readability, especially when juggling multiple tables:

-- 'mt', because myTable is too mainstream!
UPDATE myTable AS mt
SET mt.MyColumn = 'newValue'
WHERE mt.id IN (SELECT id FROM anotherTable WHERE condition = 'value');

Handling Encoding and special characters

For column names with unusual characters or a different language, ensure your database client's encoding matches with the table's to prevent mismatches.

Distinguishing between Identifiers and literals

Grasping the difference between identifiers (like column names) and string literals is crucial. If you wrongly use a backtick around 'y', it's a column name:

-- Whoops, 'y' isn't a celebrity; no need for fan quotes!
UPDATE table SET `y` = 'value'; 

-- There you go, treated as a normal citizen
UPDATE table SET column_name = 'y';