Question

My db is built as follows:

1. value1,value2,value3 | 1
2. value4,value5,val”u6 | 2
3. value 5, value 6, value 8 |3

(Two columns, one with a key separated by commas and the other just a normal var-char)

I’m looking for the most reliable way to find a query within the quotes and I’m getting kinda lost here.

I’m using the word boundaries for that:

SELECT * FROM ABC WHERE content REGEXP '[[:<:]]value 5[[:>:]]'

The problem is when I’m doing this query:

SELECT * FROM ABC WHERE content REGEXP '[[:<:]]5[[:>:]]'

It will also return the value, which is not what I’m looking for. Another problem is that the word boundaries refer to quotes as a word boundary

How can I solve this and create a simple query that will only fetch the exact full query between the quotes?

BTW
I don’t have an option to change the DB structure…

Answer 1

As @MarcB commented, you really should try to normalise your schema:

CREATE TABLE ABC_values (
  id  INT,
  content VARCHAR(10),
  FOREIGN KEY (id) REFERENCES ABC (id)
);

INSERT INTO ABC_values
  (id, content)
VALUES
  (1, 'value1'), (1, 'value2'), (1, 'value3'),
  (2, 'value4'), (2, 'value5'), (2, 'val"u6'),
  (3, 'value 5'), (3, 'value 6'), (3, 'value 8')
;

ALTER TABLE ABC DROP content;

Then, as required, you can perform a SQL join between your tables and group the results:

SELECT   id, GROUP_CONCAT(ABC_values.content) AS content
FROM     ABC LEFT JOIN ABC_values USING (id) NATURAL JOIN (
  SELECT id FROM ABC_values WHERE content = 'value 5'
) t
GROUP BY id

If it is completely impossible to change the schema, you can try FIND_IN_SET():

SELECT * FROM ABC WHERE FIND_IN_SET('value 5', content)