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CREATE TABLE test (hash CHAR(40),
digits_from_hash VARCHAR(40) AS (REGEXP_REPLACE(hash, '[^0-9]', '')));
INSERT INTO test (hash) VALUES ('9ef8ed01647767afb5e0c4c45b4c373e73f795c1');
SELECT * FROM test;
| hash | digits_from_hash |
|---|---|
| 9ef8ed01647767afb5e0c4c45b4c373e73f795c1 | 9801647767504454373737951 |