Question

I am trying to write a query for Stack Exchange’s very own Data Explorer. This query will create a temporary table containing a list of commonly misspelled words and their proper spellings and then search through the posts to find them.

Here is what I have so far (minus the comments):

DECLARE @SpellingMistakes TABLE (wrong VARCHAR(255), right VARCHAR(255))

INSERT INTO @SpellingMistakes (wrong, right)
VALUES ('ubunut', 'ubuntu')

SELECT Id as [Post Link]
FROM Posts
WHERE
    ...

And that’s where I get stuck – in the WHERE clause. I need some way of saying "if Posts.Body contains any of @SpellingMistakes.wrong". However, I’m not sure how to do that.

Note: the data explorer uses Microsoft SQL Server 2008 R2.

Answer 1

I don’t know MS SQL, but most SQL implementations have a ‘LIKE’ equivalent. So in that case, you could join the two tables and use LIKE in the JOIN condition.

SELECT Id as link
FROM Posts P JOIN SpellingMistakes S
ON P.Body LIKE '%'+S.wrong+'%'

EDIT: Assuming Posts is a large table (and SpellingMistakes is not too small either), this will take a lot of resources. One way to tackle this is to split table Posts into smaller subsets and construct multiple statements.

SELECT Id as link
FROM (SELECT * FROM Posts WHERE Id<=10000) P 
JOIN 
SpellingMistakes S
ON P.Body LIKE '%'+S.wrong+'%'

SELECT Id as link
FROM (SELECT * FROM Posts WHERE Id<=20000 and Id>10000) P 
JOIN    
SpellingMistakes S
ON P.Body LIKE '%'+S.wrong+'%'

And so on.