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database - trying to concat in the RAISE() function using || results in a syntax error

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I am trying to create a trigger that catches inserts into the Viewings table where the foreign key (viewings.location) does not correspond to an existing primary key in the Places table (places.location). The logic, from what I can tell, works as expected. However my issue comes from trying to concatenate the attempted value into the error-message in the raise function. Is this not allowed?

create trigger catchForeignKeyError BEFORE INSERT ON VIEWINGS
BEGIN
SELECT CASE 
WHEN NEW.location NOT IN (SELECT PLACES.location FROM PLACES) THEN 
RAISE(ABORT, 'Error: Insert into the VIEWINGS table references location '''||NEW.location||''' that is not found in the PLACES table.') 
END; 
END;
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In the SQLite grammar, the second parameter of the RAISE() expression is not a string but a name:

RAISE(ABORT, some_error)

Identifiers can be quoted with double quotes, and for historical reasons, SQLite accepts a string (with single quotes) where an identifier is expected, but then it must be a single string, not a string expression composed of other values:

RAISE(ABORT, "some error")

There is no mechanism to get a dynamic value into the error message, except by creating a user-defined function for this.


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