Trying to select from table where the format can be either 1/2/2014, 1-2-2014 or 1_2_2014 in a text field. There's other text involved outside of this format but it shouldn't matter, but that's why this is text not a date type.
I tried '%[-,_,/]%[-,_,/]%' which doesn't work, and I've tried escaping the special characters in the brackets such as %[-,!_,/]%[-,!_,/]%' ESCAPE '!' which also doesn't work. Any suggestions?
I wanted to avoid using three searches like,
LIKE '%/%/%'
OR '%-%-%'
OR '%!_%!_%' ESCAPE '!'
EDIT: Using SQLite3
There is no regex like behavior in using the LIKE operator in SQL. You would have use two expressions and OR them together:
select * from table
where column like '%-%-%'
or column like '%/%/%'
Thanks for the information. I ended up switching to the GLOB operator which support [] in SQLite.
The Example was altered to GLOB '?[/-_]?[/-_]??*' Where * serves as % and ? serves as _ for the GLOB function.
Also thanks to Amadeaus9 for pointing out minimum characters between delimiters so that '//' isn't a valid answer.
If you're using T-SQL (AKA SQL Server) you don't want to have commas in the character set - i.e. LIKE '%[/_-]%[/_-]%'. However, keep in mind that this can match ANYTHING that has, anywhere within it, any two characters from the set.
EDIT: it doesn't looke like SQLite supports that sort of use of its LIKE operator, based on this link.
Relevant quote:
There are two wildcards used in conjunction with the LIKE operator:
The percent sign (%)
The underscore (_)
However, you may want to take a look at this question, which details using regex in SQLite.
It is not possible using the LIKE syntax.
However Sqlite3 would support the REGEXP operator; this is syntactic sugar for calling an user defined function that actually does the matching. If provided by your platform, then you could use for example
x REGEXP '.*[/_-].*[/_-].*'
Related
I'm a bit lost.
I've had a look at the documentation but I'm not sure if you can use LIKE and pattern match in Big Query the same as SSMS.
The code shown here works in SSMS but the results are not correct in Big Query, so was wondering if there was another way to do it.
WHERE column_name NOT LIKE '[a-Z]%'
I'm looking to return strings which contain special characters or numerics.
Use REGEXP_CONTAINS instead
where not regexp_contains(column_name, r'[a-zA-Z]')
Meantime, LIKE is also supported as a comparison operator
I have been searching for a way of using Django ORM to use the SQL underscore wildcard, and do something equivalent to this:
SELECT * FROM table
WHERE field LIKE 'abc_wxyz'
Currently, I am doing:
field_like = 'abc_wxyz'
result = MyClass.objects.extra(where=["field LIKE " + field_like])
I already tried with contains() and icontains(), but that's not what I need, since what it does is adding parenthesis to the query:
SELECT * FROM table
WHERE field LIKE '%abc/_wxyz%'
Thanks!
You can use __regex lookup to build more complex lookup expressions than __contains, __startswith or __endswith (can add "i" character to beginning of each of these to make lookups case insensitive, like icontains). In your case, I think
MyClass.objects.filter(field__regex=r'^abc.wxyz$')
Would do what you are trying to do.
You can use the field__contains attribute.
for example:
MyClass.objects.filter(field__contains='abc_wxyz')
This is equivalent to:
SELECT * FROM MyClass WHERE field LIKE 'abc_wxyz'
Lord Elron's answer is incorrect. Django escapes all developer supplied wildcard characters to the LIKE-type lookups. The statement is equivalent to
SELECT * FROM MyClass WHERE field LIKE '%abc/_wxyz%'
(as the OP discovered) and the underscore has no effect.
See Escaping percent signs and underscores in LIKE statements
The field lookups that equate to LIKE SQL statements (iexact, contains, icontains, startswith, istartswith, endswith and iendswith) will automatically escape the two special characters used in LIKE statements – the percent sign and the underscore.
How am I going to use BETWEEN Operator with Text Value or what is the right syntax when you will select all products with a ProductName for example ending with any of the letter BETWEEN 'C' and 'M'?
Most SQL dialects provide the RIGHT() function. This allows you to do:
WHERE RIGHT(TextValue, 1) BETWEEN 'C' AND 'M'
If your database doesn't have this function, you can do something similar with the built-in functions. Also, the exact comparison might depend on the collation of the column/table/database/server. Sometimes comparisons are independent of case and sometimes they are dependent on case.
In case you are interested in an alternative method (which does work with the w3schools SQL editor), you can also use the LIKE operator:
WHERE ProductName LIKE '%[c-m]'
This will get you all Product Names ending on any character between C and M.
(It does work with the w3schools SQL Editor.)
In this case, the LIKE operator is using two wildcard characters:
1.%
Any string of zero or more characters.
2.[c-m]
Any single character within the specified range ([a-f]) or set
([abcdef]).
You can find more information about the LIKE operator here:
https://msdn.microsoft.com/en-us/library/ms179859.aspx
I need to find out how many rows in a particular field in my sql server table, contain ONLY non-alphanumeric characters.
I'm thinking it's a regular expression that I need along the lines of [^a-zA-Z0-9] but Im not sure of the exact syntax I need to return the rows if there are no valid alphanumeric chars in there.
SQL Server doesn't have regular expressions. It uses the LIKE pattern matching syntax which isn't the same.
As it happens, you are close. Just need leading+trailing wildcards and move the NOT
WHERE whatever NOT LIKE '%[a-z0-9]%'
If you have short strings you should be able to create a few LIKE patterns ('[^a-zA-Z0-9]', '[^a-zA-Z0-9][^a-zA-Z0-9]', ...) to match strings of different length. Otherwise you should use CLR user defined function and a proper regular expression - Regular Expressions Make Pattern Matching And Data Extraction Easier.
This will not work correctly, e.g. abcÑxyz will pass thru this as it has a,b,c... you need to work with Collate or check each byte.
I have a situation where the name column comprises of many special characters. I have a solution where I do Like with all the special characters mentioned like this '%[''",/#$!-#%^&*.\+-]%'`
But this I think is not a good way to solve the problem. Is there a way where I can use Regular Expression within SQL query itself for checking if the name column contains special characters or not. Special characters would be everything apart from alphabets and numbers.
I know Regex can be used with C# and T-SQL. Looking for something if can be done through native SQL
You can use
WHERE yourcolumn LIKE '%[^0-9a-zA-Z]%' COLLATE Latin1_General_BIN
http://msdn.microsoft.com/en-us/magazine/cc163473.aspx