Connection Timeout for SQL Server

What is Connect Timeout in sql server connection string?

That is the timeout to create the connection, NOT a timeout for commands executed over that connection.

See for instance http://www.connectionstrings.com/all-sql-server-connection-string-keywords/
(note that the property is "Connect Timeout" (or "Connection Timeout"), not just "Timeout")

From the comments:

It is not possible to set the command timeout through the connection string. However, the SqlCommand has a CommandTimeout property (derived from DbCommand) where you can set a timeout (in seconds) per command.

Do note that when you loop over query results with Read(), the timeout is reset on every read. The timeout is for each network request, not for the total connection.

Default Timeout Period in SQL Server

DbCommand has CommandTimeout, which is what you want here - it is set per command; the "connect timeout" only impacts, reasonably enough, what the timeout is for connecting. The default value for CommandTimeout on SqlCommand is 30 seconds.

sql: set connection timeout in the connection string

There are two timeouts relating to SQL connections/commands - there is a connection timeout, that affects how long a connection is willing to wait when you try to open it, and a command timeout that affects how long an individual command being executed will wait.

You need to adjust the second of these - by e.g. setting the CommandTimeout property on the SqlCommand object.

What is Entity Framework's default Connection timeout for SQL Server?

According to the Documentation when using SQL.

SqlConnetionTimeout: The default is 15 seconds.

SqlCommandTimeout: The default is 30 seconds.

A good explanation about connection and command timeouts

Connection timeout for SQL server

Yes, you could append ;Connection Timeout=30 to your connection string and specify the value you wish.

The timeout value set in the Connection Timeout property is a time expressed in seconds. If this property isn't set, the timeout value for the connection is the default value (15 seconds).

Moreover, setting the timeout value to 0, you are specifying that your attempt to connect waits an infinite time. As described in the documentation, this is something that you shouldn't set in your connection string:

A value of 0 indicates no limit, and should be avoided in a
ConnectionString because an attempt to connect waits indefinitely.

Sql Server connection timeout

The problem is with the command timeout, i solved the problem with the following line of code :

command.CommandTimeout = 30000;

but the question now : how can i set commandTimeout default value over the application

SQL Server TimeOut in C# After Adjusting timeout

Connection timeout and command timeout are two different things.

A connection timeout occurs when a connection cannot be retrieved from the connection pool within the allotted timeout period.

A command timeout occurs when a connection has been retrieved, but the query being executed against it doesn't return results within the allotted command timeout period. The default command timeout period in ADO.NET is 30 seconds.

If you've set the connection timeout to 300 seconds and you're still getting a timeout, it's likely a command timeout. As walkers01 said, set your command timeout to a suitable number of seconds. 300 seconds should be far more than sufficient; if your query executes in one minute in SSMS, a timeout of 90 seconds should suffice.