Word popularity leaderboard in SQL Server based message-board - sql-server

Question

In a SQL server database, I have a table Messages with the following columns:
Id INT(1,1)
Detail VARCHAR(5000)
DatetimeEntered DATETIME
PersonEntered VARCHAR(25)
Messages are pretty basic, and only allow alphanumeric characters and a handful of special characters, which are as follows:
`¬!"£$%^&*()-_=+[{]};:'##~\|,<.>/?
Ignoring the bulk of the special characters bar the apostrophe, what I need is a way to list each word along with how many times the word occurs in the Detail column, which I can then filter by PersonEntered and DatetimeEntered.
Example output:
Word Frequency
-----------------
a 11280
the 10102
and 8845
when 2024
don't 2013
.
.
.
It doesn't need to be particularly clever. It is perfectly fine if dont and don't are treated as separate words.
I'm having trouble splitting out the words into a temporary table called #Words.
Once I have a temporary table, I would apply the following query:
SELECT
Word,
SUM(Word) AS WordCount
FROM #Words
GROUP BY Word
ORDER BY SUM(Word) DESC
Please help.

Answer 1

Personally, I would strip out almost all the special characters, and then use a splitter on the space character. Of your permitted characters, only ' is going to appear in a word; anything else is going to be grammatical.
You haven't posted what version of SQL you're using, so I've going to use SQL Server 2017 syntax. If you don't have the latest version, you'll need to replace TRANSLATE with a nested REPLACE (So REPLACE(REPLACE(REPLACE(REPLACE(... REPLACE(M.Detail, '¬',' '),...),'/',' '),'?',' '), and find a string splitter (for example, Jeff Moden's DelimitedSplit8K).
USE Sandbox;
GO
CREATE TABLE [Messages] (Detail varchar(5000));
INSERT INTO [Messages]
VALUES ('Personally, I would strip out almost all the special characters, and then use a splitter on the space character. Of your permitted characters, only `''` is going to appear in a word; anything else is going to be grammatical. You haven''t posted what version of SQL you''re using, so I''ve going to use SQL Server 2017 syntax. If you don''t have the latest version, you''ll need to replace `TRANSLATE` with a nested `REPLACE` (So `REPLACE(REPLACE(REPLACE(REPLACE(... REPLACE(M.Detail, ''¬'','' ''),...),''/'','' ''),''?'','' '')`, and find a string splitter (for example, Jeff Moden''s [DelimitedSplit8K](http://www.sqlservercentral.com/articles/Tally+Table/72993/)).'),
('As a note, this is going to perform **AWFULLY**. SQL Server is not designed for this type of work. I also imagine you''ll get some odd results and it''ll include numbers in there. Things like dates are going to get split out,, numbers like `9,000,000` would be treated as the words `9` and `000`, and hyperlinks will be separated.')
GO
WITH Replacements AS(
SELECT TRANSLATE(Detail, '`¬!"£$%^&*()-_=+[{]};:##~\|,<.>/?',' ') AS StrippedDetail
FROM [Messages] M)
SELECT SS.[value], COUNT(*) AS WordCount
FROM Replacements R
CROSS APPLY string_split(R.StrippedDetail,' ') SS
WHERE LEN(SS.[value]) > 0
GROUP BY SS.[value]
ORDER BY WordCount DESC;
GO
DROP TABLE [Messages];
As a note, this is going to perform AWFULLY. SQL Server is not designed for this type of work. I also imagine you'll get some odd results and it'll include numbers in there. Things like dates are going to get split out,, numbers like 9,000,000 would be treated as the words 9 and 000, and hyperlinks will be separated.