Pulling the postcode area from the full postcode

Question

If I have a Postcode EH1 2GB I am looking for a function which will pull only the EH

Ideally this would work for postcodes which may only contain 1 leading letter such as G2 1AB and 2 numbers after the leading letters such as EH54 1BD and G25 2RD

I have tried using

I have tried pulling pulling the whole postcode and then using javascript (const extractPostalArea = (postalCode) => postalCode.match(/^[A-Z]+/)?.[0] ?? null;) to further separate the Postcode, however this is causing more issues than it is solving.

Is there a way to pull the postcode that would give a result similar to the below table...

Postcode	PostalArea
B2 1GH	B
EH2 4ED	EH
SL4 5FR	SL
E2W 4ST	E

Any help would be much appreciated

I am using MariaDB

Answer 1

You should be able to use the same regex in MariaDB as you did in the JavaScript by using the REGEXP_SUBSTR function, like:

SELECT REGEXP_SUBSTR(Postcode, '^[A-Z]+') AS PostalArea From CollectionAddress

The ^ ensures that the one-or-more [A-Z] has to be at the start of the string.