I am using Sql Server 2008 R2 Enterprise. I am coding an application capable of inserting, updating, deleting and selecting records from a Sql tables. The application is making errors when it comes to the records that contain special characters such as ć, č š, đ and ž.
Here's what happens:
The command:
INSERT INTO Account (Name, Person)
VALUES ('Boris Borenović', 'True')
WHERE Id = '1'
inserts a new record but the Name field is Boris Borenovic, so character ć is changed to c.
The command:
SELECT * FROM Account
WHERE Name = 'Boris Borenović'
returns the correct record, so again the character ć is replaced by c and the record is returned.
Questions:
Is it possible to make Sql Server save the ć and other special characters mentioned earlier?
Is it still possible, if the previous question is resolved, to make Sql be able to return the Boris Borenović record even if the query asks for Boris Borenovic?
So, when saving records I want Sql to save exactly what is given, but when retrieving the records, I want it to be able to ingnore the special characters. Thanks for all the help.
1) Make sure the column is of type nvarchar rather than varchar (or nchar for char)
2) Use N' at the start of string literals containing such strings, e.g. N'Boris Borenović'
3) If you're using a client library (e.g. ADO.Net), it should handle Unicode text, so long as, again, the parameters are marked as being nvarchar/nchar instead of varchar/char
4) If you want to query and ignore accents, then you can add a COLLATE clause to your select. E.g.:
SELECT * FROM Account
WHERE Name = 'Boris Borenovic' COLLATE Latin1_General_CI_AI
Where _CI_AI means Case Insensitive, Accent Insensitive, should return all rows with all variants of the "c" at the end.
5) If the column in the table is part of a UNIQUE/PK constraint, and you need it to contain both "Boris Borenović" and "Boris Borenovic", then add a COLLATE clause to the column definition, but this time use a collation with "_AS" at the end, which says that it's accent sensitive.
To allow SQL Server to store special characters, use nvarchar instead of varchar for the column type.
When retrieving, you can force a accent-insensitve collation so that it ignores the different C's:
WHERE Name = 'Boris Borenović' COLLATE Cyrillic_General_CI_AI
Here, CI stands for Case Insensitive, and AS for Accent Insensitive.
I've faced with the same problem and after some researching:
https://dba.stackexchange.com/questions/139551/how-do-i-set-a-sql-server-unicode-nvarchar-string-to-an-emoji-or-supplementary
What is the difference between varchar and nvarchar?
I altered type of needed fields:
ALTER TABLE [table_name] ALTER COLUMN column_name [nvarchar]
GO
And it works!
Related
I have seen prefix N in some insert T-SQL queries. Many people have used N before inserting the value in a table.
I searched, but I was not able to understand what is the purpose of including the N before inserting any strings into the table.
INSERT INTO Personnel.Employees
VALUES(N'29730', N'Philippe', N'Horsford', 20.05, 1),
What purpose does this 'N' prefix serve, and when should it be used?
It's declaring the string as nvarchar data type, rather than varchar
You may have seen Transact-SQL code that passes strings around using
an N prefix. This denotes that the subsequent string is in Unicode
(the N actually stands for National language character set). Which
means that you are passing an NCHAR, NVARCHAR or NTEXT value, as
opposed to CHAR, VARCHAR or TEXT.
To quote from Microsoft:
Prefix Unicode character string constants with the letter N. Without
the N prefix, the string is converted to the default code page of the
database. This default code page may not recognize certain characters.
If you want to know the difference between these two data types, see this SO post:
What is the difference between varchar and nvarchar?
Let me tell you an annoying thing that happened with the N' prefix - I wasn't able to fix it for two days.
My database collation is SQL_Latin1_General_CP1_CI_AS.
It has a table with a column called MyCol1. It is an Nvarchar
This query fails to match Exact Value That Exists.
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ'
// 0 result
using prefix N'' fixes it
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ'
// 1 result - found!!!!
Why? Because latin1_general doesn't have big dotted İ that's why it fails I suppose.
1. Performance:
Assume your where clause is like this:
WHERE NAME='JON'
If the NAME column is of any type other than nvarchar or nchar, then you should not specify the N prefix. However, if the NAME column is of type nvarchar or nchar, then if you do not specify the N prefix, then 'JON' is treated as non-unicode. This means the data type of NAME column and string 'JON' are different and so SQL Server implicitly converts one operand’s type to the other. If the SQL Server converts the literal’s type
to the column’s type then there is no issue, but if it does the other way then performance will get hurt because the column's index (if available) wont be used.
2. Character set:
If the column is of type nvarchar or nchar, then always use the prefix N while specifying the character string in the WHERE criteria/UPDATE/INSERT clause. If you do not do this and one of the characters in your string is unicode (like international characters - example - ā) then it will fail or suffer data corruption.
Assuming the value is nvarchar type for that only we are using N''
I have seen prefix N in some insert T-SQL queries. Many people have used N before inserting the value in a table.
I searched, but I was not able to understand what is the purpose of including the N before inserting any strings into the table.
INSERT INTO Personnel.Employees
VALUES(N'29730', N'Philippe', N'Horsford', 20.05, 1),
What purpose does this 'N' prefix serve, and when should it be used?
It's declaring the string as nvarchar data type, rather than varchar
You may have seen Transact-SQL code that passes strings around using
an N prefix. This denotes that the subsequent string is in Unicode
(the N actually stands for National language character set). Which
means that you are passing an NCHAR, NVARCHAR or NTEXT value, as
opposed to CHAR, VARCHAR or TEXT.
To quote from Microsoft:
Prefix Unicode character string constants with the letter N. Without
the N prefix, the string is converted to the default code page of the
database. This default code page may not recognize certain characters.
If you want to know the difference between these two data types, see this SO post:
What is the difference between varchar and nvarchar?
Let me tell you an annoying thing that happened with the N' prefix - I wasn't able to fix it for two days.
My database collation is SQL_Latin1_General_CP1_CI_AS.
It has a table with a column called MyCol1. It is an Nvarchar
This query fails to match Exact Value That Exists.
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ'
// 0 result
using prefix N'' fixes it
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ'
// 1 result - found!!!!
Why? Because latin1_general doesn't have big dotted İ that's why it fails I suppose.
1. Performance:
Assume your where clause is like this:
WHERE NAME='JON'
If the NAME column is of any type other than nvarchar or nchar, then you should not specify the N prefix. However, if the NAME column is of type nvarchar or nchar, then if you do not specify the N prefix, then 'JON' is treated as non-unicode. This means the data type of NAME column and string 'JON' are different and so SQL Server implicitly converts one operand’s type to the other. If the SQL Server converts the literal’s type
to the column’s type then there is no issue, but if it does the other way then performance will get hurt because the column's index (if available) wont be used.
2. Character set:
If the column is of type nvarchar or nchar, then always use the prefix N while specifying the character string in the WHERE criteria/UPDATE/INSERT clause. If you do not do this and one of the characters in your string is unicode (like international characters - example - ā) then it will fail or suffer data corruption.
Assuming the value is nvarchar type for that only we are using N''
I have some data in my table's column upn.
Here is a small sample set of this data.
Pasquale.Rombolà#it.eurw.domain.net
JuanMaria.RomanGonçalves#eurs.domain.net
Santo.Paternò#it.eurw.domain.net
Peter.Browne#UK.EURW.domain.net
François.ESTIN#fr.eurw.domain.net
Frédéric.Huynh#fr.eurw.domain.net
Frédérique.Psaume#fr.eurw.domain.net
Laura.PiñeiroGomez#eurs.domain.net
Maria.AranzabalSaldaña#eurs.domain.net
Alberto.RubioMuñoz#eurs.domain.net
Peter.Brüggemann#UK.EURW.domain.net
Russel.Peters#CA.domain.net
I want to query this table for UPN values where I have some special characters in the UPN. So my query should not return upns such as:
Peter.Browne#UK.EURW.domain.net
and
Russel.Peters#CA.domain.net
But returns everything else with special characters such as [à,ò,ñ,ü ...etc]
I have tried this query but it doesn't work.
Select * from TableName
Where [UPN] like %[a-z,0-9,#,\.,-,A-Z]%
It returns everything including those which don't have any special characters.
Please help.
If I understand correctly, I think you'll just need to add a "^" as the first character inside the square brackets.
At present you're saying you want to return all those UPNs where one or more characters is in the list you give (i.e. the "ordinary" characters). The "^" should reverse that and give you all the UPNs where at least one of the characters is not in the list you give.
Update: After testing locally ... Make sure your collation is "Accent Sensitive" (if necessary add "Latin1_General_CI_AS" or similar after your "like" clause.
I found it only worked if rather than "A-Z", I actually typed out the whole alphabet.
You need to add binary collate clause in it. Chose necessary collation as per your data. For given sample data Latin1_General_BIN works. Here is the link for collation in sql server.
This snippet worked for me on my machine-
create table #t (name varchar(100));
insert into #t values
('Pasquale.Rombolà#it.eurw.domain.net'),
('JuanMaria.RomanGonçalves#eurs.domain.net'),
('Santo.Paternò#it.eurw.domain.net'),
('Peter.Browne#UK.EURW.domain.net'),
('François.ESTIN#fr.eurw.domain.net'),
('Frédéric.Huynh#fr.eurw.domain.net'),
('Frédérique.Psaume#fr.eurw.domain.net'),
('Laura.PiñeiroGomez#eurs.domain.net'),
('Maria.AranzabalSaldaña#eurs.domain.net'),
('Alberto.RubioMuñoz#eurs.domain.net'),
('Peter.Brüggemann#UK.EURW.domain.net'),
('Russel.Peters#CA.domain.net');
select * from #t where name not like '%[^a-zA-Z0-9#.]%' COLLATE Latin1_General_BIN;
Output-
Peter.Browne#UK.EURW.domain.net
Russel.Peters#CA.domain.net
I have seen prefix N in some insert T-SQL queries. Many people have used N before inserting the value in a table.
I searched, but I was not able to understand what is the purpose of including the N before inserting any strings into the table.
INSERT INTO Personnel.Employees
VALUES(N'29730', N'Philippe', N'Horsford', 20.05, 1),
What purpose does this 'N' prefix serve, and when should it be used?
It's declaring the string as nvarchar data type, rather than varchar
You may have seen Transact-SQL code that passes strings around using
an N prefix. This denotes that the subsequent string is in Unicode
(the N actually stands for National language character set). Which
means that you are passing an NCHAR, NVARCHAR or NTEXT value, as
opposed to CHAR, VARCHAR or TEXT.
To quote from Microsoft:
Prefix Unicode character string constants with the letter N. Without
the N prefix, the string is converted to the default code page of the
database. This default code page may not recognize certain characters.
If you want to know the difference between these two data types, see this SO post:
What is the difference between varchar and nvarchar?
Let me tell you an annoying thing that happened with the N' prefix - I wasn't able to fix it for two days.
My database collation is SQL_Latin1_General_CP1_CI_AS.
It has a table with a column called MyCol1. It is an Nvarchar
This query fails to match Exact Value That Exists.
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ'
// 0 result
using prefix N'' fixes it
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ'
// 1 result - found!!!!
Why? Because latin1_general doesn't have big dotted İ that's why it fails I suppose.
1. Performance:
Assume your where clause is like this:
WHERE NAME='JON'
If the NAME column is of any type other than nvarchar or nchar, then you should not specify the N prefix. However, if the NAME column is of type nvarchar or nchar, then if you do not specify the N prefix, then 'JON' is treated as non-unicode. This means the data type of NAME column and string 'JON' are different and so SQL Server implicitly converts one operand’s type to the other. If the SQL Server converts the literal’s type
to the column’s type then there is no issue, but if it does the other way then performance will get hurt because the column's index (if available) wont be used.
2. Character set:
If the column is of type nvarchar or nchar, then always use the prefix N while specifying the character string in the WHERE criteria/UPDATE/INSERT clause. If you do not do this and one of the characters in your string is unicode (like international characters - example - ā) then it will fail or suffer data corruption.
Assuming the value is nvarchar type for that only we are using N''
I have seen prefix N in some insert T-SQL queries. Many people have used N before inserting the value in a table.
I searched, but I was not able to understand what is the purpose of including the N before inserting any strings into the table.
INSERT INTO Personnel.Employees
VALUES(N'29730', N'Philippe', N'Horsford', 20.05, 1),
What purpose does this 'N' prefix serve, and when should it be used?
It's declaring the string as nvarchar data type, rather than varchar
You may have seen Transact-SQL code that passes strings around using
an N prefix. This denotes that the subsequent string is in Unicode
(the N actually stands for National language character set). Which
means that you are passing an NCHAR, NVARCHAR or NTEXT value, as
opposed to CHAR, VARCHAR or TEXT.
To quote from Microsoft:
Prefix Unicode character string constants with the letter N. Without
the N prefix, the string is converted to the default code page of the
database. This default code page may not recognize certain characters.
If you want to know the difference between these two data types, see this SO post:
What is the difference between varchar and nvarchar?
Let me tell you an annoying thing that happened with the N' prefix - I wasn't able to fix it for two days.
My database collation is SQL_Latin1_General_CP1_CI_AS.
It has a table with a column called MyCol1. It is an Nvarchar
This query fails to match Exact Value That Exists.
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ'
// 0 result
using prefix N'' fixes it
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ'
// 1 result - found!!!!
Why? Because latin1_general doesn't have big dotted İ that's why it fails I suppose.
1. Performance:
Assume your where clause is like this:
WHERE NAME='JON'
If the NAME column is of any type other than nvarchar or nchar, then you should not specify the N prefix. However, if the NAME column is of type nvarchar or nchar, then if you do not specify the N prefix, then 'JON' is treated as non-unicode. This means the data type of NAME column and string 'JON' are different and so SQL Server implicitly converts one operand’s type to the other. If the SQL Server converts the literal’s type
to the column’s type then there is no issue, but if it does the other way then performance will get hurt because the column's index (if available) wont be used.
2. Character set:
If the column is of type nvarchar or nchar, then always use the prefix N while specifying the character string in the WHERE criteria/UPDATE/INSERT clause. If you do not do this and one of the characters in your string is unicode (like international characters - example - ā) then it will fail or suffer data corruption.
Assuming the value is nvarchar type for that only we are using N''