Find the brackets

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Find the brackets

Steve Jones - SSC Editor

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November 16, 2016 at 8:20 pm

#331921

Comments posted to this topic are about the item Find the brackets
November 17, 2016 at 4:49 am

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Jeff Moden SSC Guru Points: 1004581 More actions · Answer 1

IMHO, cleaner code if you take the shortcut.

SELECT mychar FROM mydata WHERE mychar LIKE '[[]%'

--Jeff Moden

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TimCarrett Default port Points: 1484 More actions · Answer 2

I tried this against a SQL Server 2008 R2 database and both 1 and 5 brought back the bracketed records. Luckily I choose answer 1.

Neil Burton SSC-Insane Points: 23054 More actions · Answer 3

TimCarrett (11/17/2016)
I tried this against a SQL Server 2008 R2 database and both 1 and 5 brought back the bracketed records. Luckily I choose answer 1.

Query 5 will bring back records that have characters before the bracket too. The question was for rows that begin with a bracket. Although in the example posted it brings back the same rows, if you run the queries against the table below the outcome will be different.

CREATE TABLE #MyData

(

mychar VARCHAR(50)

);

GO

INSERT #MyData

(mychar)

VALUES

('This is a string'),

('"A Quoted String"'),

('''Single quoted string'''),

('''more single quotes'''),

('AA[My bracketed string]'),

(''),

('[Can I find this string]')

;

GO

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DamianC SSCrazy Eights Points: 8023 More actions · Answer 4

Wasn't aware of ESCAPE as I would have used '[[]%'

- Damian

TheTrojan SSC Eights! Points: 836 More actions · Answer 5

Hi Steve,

it seems to me that there are a couple of minor mistakes in the solution: "The only query that will return the two rows is the one that uses the ESCAPE option ".

The rows returned are three, not two. Then I think that it would be better to say that the query n.5 returns the three rows as well, but the logic is not correct: in a bigger table it would return also strings like "xyq[My...", "1[Can..." because of the "%".

Grasshoppers like me could be confused

Toreador SSChampion Points: 11375 More actions · Answer 6

I'm assuming there was a typo in one of the options and it was meant to have a character before the initial bracket, so the correct answer would have returned 2 rows and the final option would have been clearly wrong as it returned 3.

Personally I'd use one of the alternatives suggested in the explanation as I think it's clearer

SELECT mychar FROM mydata WHERE mychar LIKE '![%' ESCAPE '!'

Ed Wagner SSC Guru Points: 287026 More actions · Answer 7

Nice question on one of the basics of strings. Thanks, Steve.

Tally Tables - Performance Personified
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Laurie Dunn Ten Centuries Points: 1101 More actions · Answer 8

This would also work and keep the code simple...

SELECT *

FROM dbo.MyData

WHERE Left(mychar,1)='[';

funbi SSCarpal Tunnel Points: 4992 More actions · Answer 9

Laurie Dunn (11/17/2016)
This would also work and keep the code simple...
SELECT *
FROM dbo.MyData
WHERE Left(mychar,1)='[';

Yeah I got

select * from MyData where CHARINDEX('[',mychar,0) = 1

which works fine, then looked at the options and realised today's lesson was about ESCAPE :hehe:

m mcdonald Hall of Fame Points: 3264 More actions · Answer 10

Jeff Moden (11/16/2016)
IMHO, cleaner code if you take the shortcut.
SELECT mychar FROM mydata WHERE mychar LIKE '[[]%'

That's how I went about doing it and then had to take a closer look at the possible answers

Cheers

Luis Cazares SSC Guru Points: 183706 More actions · Answer 11

funbi (11/17/2016)
Laurie Dunn (11/17/2016)
This would also work and keep the code simple...
SELECT *
FROM dbo.MyData
WHERE Left(mychar,1)='[';
Yeah I got
select * from MyData where CHARINDEX('[',mychar,0) = 1
which works fine, then looked at the options and realised today's lesson was about ESCAPE :hehe:

Both of these queries are non SARGable, which would result in an index scan instead of an index seek.

Luis C.
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funbi SSCarpal Tunnel Points: 4992 More actions · Answer 12

Luis Cazares (11/17/2016)
funbi (11/17/2016)
Laurie Dunn (11/17/2016)
This would also work and keep the code simple...
SELECT *
FROM dbo.MyData
WHERE Left(mychar,1)='[';
Yeah I got
select * from MyData where CHARINDEX('[',mychar,0) = 1
which works fine, then looked at the options and realised today's lesson was about ESCAPE :hehe:
Both of these queries are non SARGable, which would result in an index scan instead of an index seek.

The table has 7 rows.

Find the brackets

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