I'm trying to escape an underscore in a like operator but not getting any results. I'm trying to find any rows with a value like 'aa_'.
WHERE value LIKE '%aa\\_%'
Use ESCAPE:
Wildcard characters can be escaped using the single character specified for the ESCAPE parameter.
WITH dataset (str) AS (
VALUES ('aa_1'),
('aa_2'),
('aa1')
)
SELECT *
FROM dataset
WHERE str like 'aa\_%' ESCAPE '\'
Output:
str
aa_1
aa_2
Related
I have a query like this which is not retrieving the values from DB table even if the required value exist there.
Here's the query, which return zero rows:
Select * from SitePanel_FieldValue WHere SiteFieldIdfk =111
And SiteFieldvalue like '%!##$%&*()-_=+{}|:"<>?[]\;'',./%'
Following is the value in the table:
'!##$%&*()-_=+{}|:"<>?[]\;'',./'
When I run the query without ";" it is returning the value.
Can any one help me in figuring this out?
Thanks
Ritu
You are using multiple characters which are reserved when using LIKE statement.
i.e. %, _, []
Use the escape character clause (where I have used backtick to treat special characters as regular) such as
Select * from SitePanel_FieldValue WHere SiteFieldIdfk =111
And SiteFieldvalue like '%!##$`%&*()-`_=+{}|:"<>?`[`]\;'',./%' escape '`'
The value in your table is:
!##$%&*()-_=+{};; :"<>?[]\;'',./
And the one in the like is:
(!##$%&*()-_=+{};;
Starting with ( it will never match, also you should scape the percent (%) in the middle of the string like this:
Select *
FROM SitePanel_FieldValue
WHERE SiteFieldIdfk =111
AND SiteFieldvalue like '%!##$\%&*()-_=+{};;%' ESCAPE '\'
The problem is your brackets ([]), it has nothing to do with semicolons. If we remove the brackets, the above works:
SELECT CASE WHEN '!##$%&*()-_=+{}|:"<>?\;'',./' LIKE '%!##$%&*()-_=+{}|:"<>?\;'',./%' THEN 1 END AS WithoutBrackets,
CASE WHEN '!##$%&*()-_=+{}|:"<>?[]\;'',./' LIKE '%!##$%&*()-_=+{}|:"<>?[]\;'',./%' THEN 1 END AS WithBrackets
Notice that WithoutBrackets returns 1, where as WithBrackets returns NULL.
Brackets in a LIKE are to denote a pattern. For example SomeExpress LIKE '[ABC]' would match the characters, A, B, and C. If you are going to include special characters, you need to ESCAPE them. You have both brackets, a percent sign (%) and an underscore (_) you need to escape. You don't need to escape the hyphen (-), as it doesn't appear in a pattern (for example [A-Z]). I choose to use a backtick as the ESCAPE character, as it doesn't appear in your string, and demonstrate with a CASE expression again:
SELECT CASE WHEN '!##$%&*()-_=+{}|:"<>?[]\;'',./' LIKE '%!##$`%&*()-`_=+{}|:"<>?`[`]\;'',./%' ESCAPE '`' THEN 1 END;
If you wanted to use a backslash (\ ), which many do, you would need to also escape the backslash in your string:
SELECT CASE WHEN '!##$\%&*()-_=+{}|:"<>?[]\;'',./' LIKE '%!##$%&*()-\_=+{}|:"<>?\[\]\\;'',./%' ESCAPE '\' THEN 1 END;
db<>fiddle
I think the issue is actually with the backslash. This is an escape character and so if you want it to be included, you have to put it in twice.
Select * from SitePanel_FieldValue WHere SiteFieldIdfk =111
And SiteFieldvalue like '%!##$%&*()-_=+{}|:"<>?[]\\;'',./%'
I would like to run a query like the following on Amazon Athena
Select * from my_table
where my_table.my_field like '%'sample_text'%'
I want to match the single quotes and the underscore in 'sample_text'.
I've tried variations of escape characters like \_, \\_, [_], `_, and `_` without success.
Is this possible?
To escape special characters in LIKE use ESCAPE parameter:
Wildcard characters can be escaped using the single character specified for the ESCAPE parameter.
WITH dataset (str) AS (
VALUES ('sample_text '),
('sample text ')
)
SELECT *
FROM dataset
WHERE str like 'sample\_text%' ESCAPE '\'
Output:
str
sample_text
I have the following value in a db column:
some%thing
I'm using h2 and postgres, but can't figure out why this query, where I have escaped the % to perform a literal search, is not matching the row highlighted?:
LIKE 'some\%thing'
Because 'value' is a character string literal and not the name of your column. You need to use double quotes instead.
"value" LIKE 'some\%hing'
One option is to use regular expressions:
where value ~ '%'
LIKE also supports an explicit escape character:
where value like '%$%%' escape '$'
Or the default one, \.
SELECT *
FROM performance_table
WHERE ad_group like '%|%'
I have no idea on how to escape the Pipe operator here.
You don't need to escape | in T-SQL as it has no special meaning inside like. However, if for example you would like to find texts containing % character, what you're looking for is:
SELECT *
FROM performance_table
WHERE ad_group like '%#%%' escape '#'
where escape defines escape character.
The pipe character does not need to be escaped.
Your query will find all records that contain a pipe character in the ad_group column.
When used inside a string literal ('|'), the character is not treated as an operator. Its function as an operator is bitwise OR, as for example in
select 8|3
will be 11.
I need to include the special character "%" in my LIKE clause in a SQL query, e.g.:
Select * From Some_Table Where Field_Name Like 'bla%bla&2';
How do I write that?
If you want to match Field_Name values that contain 'bla%bla&2', then you need to write this:
set define off
Select * From Some_Table Where Field_Name Like '%bla\%bla&2%' escape '\';
You get to specify which character you want to use to escape a following character (thanks should go to mathguy, not me). You also have to set define off to prevent sqlplus from trying to substitute values in a string.
If, however, you want to match Field_Name values that exactly equal the given string, then you do this instead:
set define off
Select * From Some_Table Where Field_Name = 'bla%bla&2';
If I am not mistakend you escape them with a backslash (\)
Select * From Some_Table Where Field_Name Like 'bla\%bla&2' ESCAPE '\';
Use escape \ to treat is a literal
SELECT *
FROM Some_Table
WHERE Field_Name LIKE 'blah\%'|| 'blah' ||'&'|| '2';
I'll guess that you're using a tool which treats &n, where n is a digit, as a variable marker. If you're using SQL*Plus or SQL Developer you'd need to issue the SQL*Plus command SET DEFINE OFF. Other tools may use other methods to accomplish this.
Best of luck.
I do not think the backslash escape character will work here for the ampersand. Instead, you will want to divide your search into concatenated strings using double pipes. Use single quotes around each piece of literal text. Next, replace the & with chr(38) which is the ampersand. You can see this with:
select chr(38) from dual
You will still want to include the backslash before the % and finish your statement with escape '\'. Notice, I did not quote the chr(38).
select * From Some_Table Where Field_Name Like 'bla\%bla'||chr(38)||'bla' escape '\'