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Nested vs unnested Replace Query
In relation to the nested replace removing the prepositions Would it make any difference to the output if rather than using:
"SELECT media_id, title, category, img FROM Media WHERE category = ?"); ORDER BY REPLACE( REPLACE( REPLACE(title, 'The ',' ') 'An ', ' '),'A ', ' '))";
We used unnested replaces like this:
REPLACE (title, 'The ', ' '); REPLACE( title, 'An ', ' ' ); REPLACE( title, 'A ', ' ' );
Just can't wrap my head around why we need to nest them.
Thanks for your time.
I hope I can make this make sense.
You are ordering by title, which you only reference once, in the innermost REPLACE, which filters out "The" in the ORDER BY sorting.
Then, the same title (void of "The") is passed to the next/parent REPLACE to filter out "An".
Then, the same title (void of both "The" and/or "An") is passed to the next/parent REPLACE to filter out "A".
In the end, you end up sorting by each catalog item's title, ignoring any "The", "An", and/or "A" that could be in it.
Another way to think of it is that the result of the innermost REPLACE becomes the first argument in the parent REPLACE, etc. all the way up the REPLACE nesting chain.
var title = "The An A Catalog Title"; title = title.replace("The ", ""); title = title.replace("An ", ""); title = title.replace("A ", ""); console.log(title);
Which will log:
title being what each title would look like to the ORDER BY sort
Does that make sense?
I hope that helps.
Stay safe and happy coding!