A collation is a set of rules that determine how data is sorted and compared for comparing characters in a character set.

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How to change SQL Server collation

How could I change the SQL Server 2008 R2 Express Default Collation for the whole server and a particular database? Is there a way to do it using visual interface of SQL Server Management Studio? In ...
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Which collation should I choose for a muiti-language website?

Does a collation have any influence over a query speed? Does the size of a table change depending of the collation? If I want to build a website that must support all possible languages (lets take ...
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Why are non-digits LIKE [0-9]?

My server's default collation is Latin1_General_CI_AS, as determined by this query: SELECT SERVERPROPERTY('Collation') AS Collation; I was surprised to discover that with this collation I can match ...
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SQL Server 2005/2008 UTF-8 Collation/Charset

I can't find option(s) directly to set UTF-8 rellated Collations/Charsets in SQL Server 2005/2008, same as is possible to set in another SQL engines, but in SQL Server 2005/2008 are there only Latin ...
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Why would you index text_pattern_ops on a text column?

Today Seven Databases in Seven Weeks introduced me to per-operator indexes. You can index strings for pattern matching the previous queries by creating a text_pattern_ops operator class index, as ...
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Treating certain Arabic characters as identical

In Arabic we have characters like ا (alef) and أ (alef with hamza). Users write them interchangeably and we want to search them interchangeably. SQL Server treats them as separate characters. How ...
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Moving from SQL 2005 [SQL_Latin1_General_CP1_CI_AS] to 2008 - will I lose any features by using 'backwards compatibility'

We're moving from SQL 2005 [Instance and DB have collation of SQL_Latin1_General_CP1_CI_AS] to SQL 2008 [which defaults to Latin1_General_CI_AS]. I completed a SQL 2008 R2 installation, and used ...
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1answer
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How to determine the collation of a table in PostgreSQL?

I want to script a check of the collations used on my tables in PostgreSQL, but googling for Postgresql detect collation is not working well for me, and the documentation is not making this an easy ...
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535 views

Dependant T-SQL comparison collation

Is there any way to set the collation for a string comparison based on an independent variable or column value? Something akin to SELECT COL1, col2 FROM [TABLE] WHERE COL3 LIKE '%string%' ...
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How to choose a collation for international database?

I'm designing a database which will store data in different languages (using UTF-8), so I think the best way to display the queries results is ordering it according to the user's language during the ...
5
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1answer
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sql_slovak_cp1250_ci_as vs Slovak_CI_AS

Can someone explain to me what is the difference between collation sql_slovak_cp1250_ci_as vs Slovak_CI_AS? I have a db set to sql_slovak_cp1250_ci_as and shared hosting supports only Slovak_CI_AS. ...
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SQL Server ; working around collation mismatches

Imagine the following scenario: I have two servers which are on two separate private networks. A linked server has been created, and there is a table in server A which has an updated version of the ...
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Is there a (non-binary) MySQL collation that doesn't treat different mathematical symbols as the same character?

I've run into a real headache with MySQL's collations and non-BMP characters (ones with Unicode codepoints above U+FFFF). Basically, given a table and data like: CREATE TABLE `math` ( `id` int(11) ...
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1answer
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MySQL: Illegal mix of collations

I've tried using a stored procedure to create indices, and got the following error: ERROR 1267 (HY000): Illegal mix of collations (utf8_general_ci,IMPLICIT) and ...
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1answer
297 views

SQL Server: TSQL or safe steps needed: Change collation en masse for group of tables

Looking for a safe TSQL (preferred) or safe steps (rather automated if possible) to change collation on dozens of tables in one throw. Background: We have a db, SQL Server 2005, with ~100 tables. ...
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Why is my PostgreSQL ORDER BY case-insensitive?

I have Postgres 9.4.4 running on Debian and I get the following ORDER BY behavior: veure_test=# show LC_COLLATE; lc_collate ------------- en_US.UTF-8 (1 row) veure_test=# SELECT ...
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3answers
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Is there a collation to sort the following strings in the following order 1,2,3,6,10,10A,10B,11?

I have a database with a VARCHAR column that contains integers of varying length. I want to sort them so 10 comes after 9, not 1, and 70A comes after 70. I was able do this with PATINDEX(), a CTE, and ...
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SQL Server Collation for Arabic, Hebrew, English and French

I have new SQL Server database which need to have support in 3 different languages. What character sets and collations do I need to choose if I want my database to support the following: Hebrew ...
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1answer
748 views

Converting a Unicode value to a non-Unicode value (SQL Server)

Unicode 9619 is a character called "Dark shade" (http://unicode-table.com/en/search/?q=9619) ▓. Using the SQL_Latin1_General_CP1_CI_AS collation and 1252 code page, I would expect that casting / ...
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1answer
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How do I resolve Postgresql error, 'no collation was derived for column “foo” with collatable type citext'?

Just recently I upgraded from Postgresql 8.4.11 to 9.1.3. I used pg_dump in the process. Now I'm getting an error: ERROR: no collation was derived for column "vin" with collatable type citext ...
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PL/pgSQL - Indexes vs Collation vs Pattern Ops

I'm using PostgreSQL 9.3. Having already read articles and answers on DBA stackexchange: Why would you index text pattern ops on a text column PostgreSQL documentation: Indexes - Opclass Pattern ...
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What's the meaning of the Collation Code (blank, 90, 100, 110) in SQL Server 2012

During the installation of SQL Server 2012, in the Collation tab, i can choose between French_CI_AS and French_100_CI_AS. What do they mean and which one is newer? When there's no Code, is it newer ...
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Latin1_General_BIN performance impact when changing the database default collation

I have set the database collation to Latin1_General_BIN, to make string comparisons case-sensitive. Will this have an impact on performance? Will it have any impact on DML or DDL operations in the ...
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Installed SQL Server 2000 with wrong collation.. how to correct for entire server instance?

I installed SQL 2000 Developer (yes, old, don't ask) on my laptop ... with the wrong collation. Oops! It's showing Latin1_General_CI_AS, but it turns out I need to use SQL_Latin1_General_CP1_CI_AS ...
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How can I extract a lessequal char from SQL_Latin1_General_CP1_CI_AS?

When I create a table like this create table char_test( item varchar(10) collate SQL_Latin1_General_CP1_CI_AS ) go I can store varchars containing ≥ insert into char_test values ('≥'); When ...
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1answer
772 views

Dutch characters in DB2 problem

Ok, first of all, I have really limited knowledge about databases. Problem that I have is next: I inserted few rows with data that contains Dutch characters, such as names of different countries. ...
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Using collate: When to use and when not to use

In one of my applications we had tsql like shown below SELECT DISTINCT [Dblist].[DbName] AS [DbName] FROM [Common].dbo.[Dblist] WHERE dbname not in ( SELECT [name] FROM ...
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1answer
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Set value of character_set_client to utf8mb4

I'm trying to convert my DB to utf8mb4 by following this guide. I have set: [client] default-character-set = utf8mb4 [mysql] default-character-set = utf8mb4 [mysqld] init-connect='SET NAMES ...
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Multiple charsets and Collations for a Multinational Database

After decades of business speaking with companies that adhere to the general Latin1 Collation, my company is facing the issue of storing information in a different charset and collation: Greek. So, ...
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How is encoding done in SQL database tables for pattern matching?

Are strings in table columns represented as bit patterns or Unicode? Does the database engine bring them into memory in a different representation character set from the disk-persisted ...
3
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779 views

Casesensitive vs. Caseinsensitive Collatesequences?

I just started working with the SQLite database places.sqlite. Fact is that this database uses case sensitive collate sequences making writing queries as funny as in Oracle. I want to know, are ...
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utf8mb4 in SQL Server Express

We have some web applications based on databases using utf8mb4 as character set and utf8mb4_Standard as collation. We saw that we can use any character we want with this setting. In SQL Server ...
2
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1answer
90 views

Why does MS SQL Server return a result for empty string check when Unicode string is not empty

select * from (select N'ግዜ ' as t) as t2 where t= '' the string 'ግዜ ' matches the above check, why is this?
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1answer
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Was using `set datcollate='C'` a mistake?

In a pre-production environment running django 1.6 on PostgreSQL 9.1 we had a problem with database records arriving in a different order from what the application was expecting. So we ran this ...
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1answer
59 views

PosgtreSQL - Change multiple fields collation in one query

I have small database with few text fields with "default" collation. I don't want to recreate database. What is the query to alter all problematic fields at once? To change the single one I can use ...
2
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1answer
158 views

Why cp1256 collation is not 1 byte in MySQL?

I've read an article that cp1256 collation takes 1 byte for Arabic characters, but when I created an index on the column that was cp1256 with type of varchar(900), only 767 characters picked up for ...
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SQL Server 2008 collation arabic

We are currently having a problem loading arabic into a SQL Server 2008 database. We want to load بِسْمِ اللَّهِ الرَّحْمَٰنِ الرَّحِيمِ but in the database it changes to بِسْمِ اللَّهِ ...
2
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1answer
67 views

Is worth change databases collation from Latin1_General to Modern spanish, migrating to a new server

We are migrating 3 databases tables from Sql Server 2000 to a new sqlserver 2014. I know that for new databases the recommended Collation for spanish is Modern_Spanish. But what is the recommendation ...
2
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1answer
228 views

What is the impact of LC_CTYPE on a PostgreSQL database?

So, I've few Debian servers with PostgreSQL on it. Historically, those servers and PostgreSQL are localized with the Latin 9 charset and back then it was fine. Now we have to handle things like ...
2
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1answer
106 views

Help Changing Collate of ALL databases

I have approximately 80 Databases with various collations. I would like to modify the collation of all 80 databases. I have the following code: USE [COLLATE_ADM] GO SET ANSI_NULLS ON GO SET ...
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What's the differences between utf8_general_ci and utf8_unicode_ci and utf8_binary collation in MySQL?

I'm can't find the documentation of MySQL on this topic. Anyone can give some explanations please?
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1answer
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Unicode support of PostgreSQL and its performance

How is the Unicode support of PostgreSQL? If I want to save Unicode data does it have to go through the conversion process while storing and retrieving? If yes then what is the performance of such ...
2
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1answer
86 views

Operator “~<~” uses varchar_pattern_ops index while normal ORDER BY clause doesn't?

Let's say I have a table with 1 000 000 records. Structure of table is: create table individual ( id serial primary key, surname varchar(128), "name" varchar(128), patronymic ...
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changing TEMPORARY TABLE default collation

when I use CREATE TEMPORARY TABLE to create a temporary table, the collation of this table is utf8_unicode_ci by default. why by default it is utf8_unicode_ci? How can I change the default?
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Why are there different levels of MySQL collation/charsets?

Looking at the MySQL server variables the server and database collation are set to latin1_swedish_ci but the collaction_connection is utf8_general_ci. Additionally, the collation/charset is set at ...
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SQL Server 2005 collation issue during installation

Every time I try to install SQL Server 2005 on to a Windows 7 machine it installs properly but the collation installed is sql_latin1_general_as instead of sql_latin1_general_cp1_ci_as. I have read ...
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Performance Implications of Explicit Collation Conversions across Linked Servers

I locally host host databases from two vendors on two different SQL instances, but on the same network. These servers frequently communicate with each other (through joins and whatnot), so we have ...
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1answer
80 views

Should I use utf8_unicode_ci or utf8_slovak_ci?

I was using utf8_slovak_ci collation until now, but I read that utf8_unicode_ci sorts very wide range of languages. Does it mean, I do not need to use separate collation for every language and I can ...
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0answers
153 views

Avoiding Functions() in the Where clause

Okay, while analyzing queries against a SQL Server 2008 R2 database, I happened upon the following query: (@p__linq__0 nvarchar(4000)) SELECT TOP (1) [Extent1].[OrderSOId] AS [OrderSOId], [Extent1] ...
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SQL fulltext accent insensitive [closed]

I am using SQL Server fulltext containstable and the column which is indexed has collation Czech_CS_AS, so why when I have word "byt" it returns records with word "být" too. I thought that the ...