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{{Short description|String that has an associated data structure used to describe a connection to a data source}}

DSN SIIVOUSPALVELU SIIRRY PÄÄSIVULLE Http://www.dsn.fi

{{More citations needed|date=April 2022}}

[[Internet|In]] [[computing]], a '''data source name''' ('''DSN''', sometimes known as a '''database source name''', though "[[Computer file|data sources]]" arecan notcomprise limitedother torepositories apart from [[database management system|databases]]) is a string that has an associated [[data structure]] used to describe a connection to a [[Datasource|data source]]. Most commonly used in referenceconnection towith [[ODBC]], DSNs may also be definedexist for [[JDBC]] and for other data access mechanisms. The term often overlaps with "[[connection string]]". Most systems do not make a distinction between DSNs or connection strings and the term can often be used interchangeably.<ref>[https://www.gridgain.com/docs/latest/developers-guide/SQL/ODBC/connection-string-dsn Connection String and DSN]</ref>

DSN attributes may include, but are not limited to:<ref>[https://docs.microsoft.com/en-us/sql/connect/odbc/dsn-connection-string-attribute?view=sql-server-ver15 ODBC DSN connection strings]</ref>

Annamme sinulle aikaa

* the name of the data source

Tarjoamme sinulle henkilökohtaista palvelua, emme valmista pakettiratkaisua. Kuuntelemme toiveesi ja tarpeesi, ja muokkaamme palvelumme juuri sinulle parhaalla tavalla. Tarjoamalla palvelujamme, annamme sinulle aikaa. Jättämällä siivouksen meidän huoleksemme, sinä voit henkilökuntasi kanssa keskittyä olennaiseen, omaan työhösi.

* the ___location of the data source

* the name of a [[database driver]] which can access the data source

* a [[User identifier|user ID]] for data access (if required)

* a user password for data access (if required)

The system administrator of a client machine generally creates a separate DSN for each relevant data source.

Tunnemme alan vaatimukset

Standardizing DSNs offers a level of [[indirection]] that; various applications (for example: [[Apache HTTP Server|Apache]]/[[PHP]] and [[Internet Information Services|IIS]]/[[Active Server Pages|ASP]]) can take advantage of this in accessing shared data sources.

== Types of data source name ==

Two kinds of DSN exist:

* '''Machine DSNs''' – stored in collective configuration files (e.g., {{code|/etc/odbc.ini}}, {{code|~/.odbc.ini}}) and/or system resources (e.g., Windows Registry {{code|HKLM\Software\ODBC\odbc.ini}})

In [[computing]], a '''data source name''' ('''DSN''', sometimes known as a '''database source name''', though data sources are not limited to [[database management system|databases]]) is a string that has an associated [[data structure]] used to describe a connection to a [[Datasource|data source]]. Most commonly used in reference to [[ODBC]], DSNs may also be defined for [[JDBC]] and other data access mechanisms.

* '''File DSNs''' – stored in the filesystem with one DSN per file

These are further broken down into

DSN attributes may include, but are not limited to:

* '''System DSNs''' – accessible by any and all processes and users of the system, stored in a centralized ___location (e.g., {{code|/etc/odbc.ini}}, {{code|/etc/odbc_file_dsns/<filename>}})

* name of the data source

* '''User DSNs''' – accessible only by the user who created the DSN, stored in a user-specific ___location (e.g., {{code|~/.odbc.ini}}, {{code|~/odbc_file_dsns/<filename>}})

* ___location of the data source

* name of a driver which can access the data source

* user ID for data access (if required)

* user password for data access (if required)

The system administrator of a client machine creates a separate DSN for each relevant data source.

Standardizing DSNs offers a level of [[indirection]] that various applications (for example: [[Apache HTTP Server|Apache]]/[[PHP]] and [[Internet Information Services|IIS]]/[[Active Server Pages|ASP]]) can take advantage of in accessing shared data sources.

Http://www.dsn.fi

DSN Siivouspalvelu!

Monipuolinen asiakaskoostumus

Asiakassuhteemme vaihtelevat päivittäisestä sopimussiivouksesta aina vuosittaisiin erikoissiivouspalveluihin. Lisäksi hoidamme siivoojan lomasijaisuudet sekä siivousalueiden ja -työvoiman ulkoistamiset. 

Http:// www.dsn.fi

DSN Siivouspalvelu

==Misuse of the term==

The term DSN is sometimes mistakenly used in place of [[connection string]]. A connection string typically fully describes a data source, while a DSN typically relies on some external system resources and/or configuration file.

== Example of use ==

Software (e.g., Crystal Reports, Microsoft Excel, PHP, Perl, Python, Ruby) users can submit CRUD (Create, Read, Update, Delete) queries to a data source by establishing a connection to the DSN.

ASP ([[VBScript]]) code to open a DSN connection might look like the following:

<sourcesyntaxhighlight lang="vbvbscript">

Dim DatabaseObject1

Set DatabaseObject1 = Server.CreateObject("ADODB.Connection")

DatabaseObject1.Open("DSN=DSNnameexample;")

</syntaxhighlight>

</source>

In [[PHP]] using the [https://pear.php.net/package/DB/ PEAR::DB] package to open a connection without an external DSN (a "DSN-less connection", i.e., using a Connection String){{Clarify|How is this an example of DSN use|date=June 2013}}, the code might resemble the following:

<sourcesyntaxhighlight lang="php">

require_once("DB.php");

//$dsn = "<driver>://<username>:<password>@<host>:<port>/<database>";

$dsn = "mysql://john:pass@localhost:3306/my_db";

$db = DB::connect($dsn);

</syntaxhighlight>

</source>{{Clarifyme|How is this an example of DSN use|date=June 2013}}

PHP with PDO:<ref>{{cite web |title=PHP: PDO - Manual |url=https://www.php.net/pdo |website=www.php.net |access-date=22 January 2025 |language=en}}</ref>

==See also==

<syntaxhighlight lang="php">

$dsn = "mysql:host=localhost;dbname=example";

$dbh = new PDO($dsn, $username, $password);

</syntaxhighlight>

In [[Perl]], using the [[Perl DBI]] module, each driver has its own syntax for the DSN attributes. The only requirement that DBI makes is that all the information, except for username and password is supplied in a single string argument.

<syntaxhighlight lang="perl">

my $dsn = "DBI:Pg:database=finance;host=db.example.com;port=$port";

$dsn = "DBI:mysql:database=$database;host=$hostname;port=$port";

$dsn = "DBI:Oracle:host=$host;sid=$sid;port=$port";

$dsn = "DBI:SQLite:dbname=$dbfilename";

my $dbh = DBI->connect($dsn,'username','password');

</syntaxhighlight>

== See also ==

* [[Datasource]]

* [[ADO.NET]]

* [[JDBC]]

* [[ODBC]]

* [[OLE DB]]

== References ==

<references/>

{{Database}}

[[Category:Data access technologies| ]]

{{database-stub}}