How to iterate through multiple client codes and execute a LIMIT 1 query for each in a single SQL query?

I have a SQL query that fetches one row (LIMIT 1) for a specific client code from the TABLEA based on several conditions. Here’s the query:

SELECT
    `TABLEA`.`client_code`
FROM
    `TABLEA`
WHERE
(
    `TABLEA`.`accounting_date` = 202408
    AND (
        `TABLEA`.`FLAG1` = ''
        OR `TABLEA`.`FLAG1` IS NULL
    )
    AND `TABLEA`.`client_code` ='A12'
    AND (
        `TABLEA`.`FLAG2` = ''
        OR `TABLEA`.`FLAG2` IS NULL
    )
    AND (
        `TABLEA`.`FLA3` = ''
        OR `TABLEA`.`FLA3` IS NULL
    )
    AND (
        `TABLEA`.`payment_closing_flag` = ''
        OR `TABLEA`.`payment_closing_flag` IS NOT NULL
    )
    AND NOT (
        `TABLEA`.`FLAG4` = 1
        AND `TABLEA`.`FLAG4` IS NOT NULL
        AND `TABLEA`.`record_status` = 'D'
        AND `TABLEA`.`record_status` IS NOT NULL
        AND `TABLEA`.`ABC_CODE` IN (0, 370, 380, 390, 400, 410, 420, 900)
        AND `TABLEA`.`ABC_CODE` IS NOT NULL
    )
) LIMIT 1;

The query works for a single client_code, but I want to execute it for multiple client_code values (e.g., ‘A12’, ‘A13’, ‘A14’, etc.) and retrieve the LIMIT 1 result for each of those client codes.

Here are my constraints:

I cannot use GROUP BY or DISTINCT due to the large number of rows (millions per client), and I only need to check the existence of one record for each client code.
Performance is critical, and using DISTINCT or GROUP BY is too slow for this dataset.
Is there a way to iterate over multiple client codes and execute this LIMIT 1 query for each client code in a single query or within a single execution block?

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