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POAny way to speed up this UPDATE? C#, SQL, T-SQL
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  1. POAny way to speed up this UPDATE? C#, SQL, T-SQL
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    copied!<p>SQL:</p> <pre><code>CREATE FUNCTION dbo.fnRandomForeNames () RETURNS VARCHAR(50) AS BEGIN RETURN ( SELECT TOP 1 [FirstName] FROM [tmp_ForeNames] ORDER BY (SELECT new_id from GetNewID) ) END GO </code></pre> <p>Similar functions for dbo.fnRandomSurNames() etc.</p> <pre><code>UPDATE Table1 SET firstname = dbo.fnRandomForeNames(), lastname = dbo.fnRandomSurNames(), address1 = dbo.fnRandomAddress1(), address2 = dbo.fnRandomAddress2(), address3 = dbo.fnRandomAddress3(), birthdate = DATEADD(DAY, ABS(CHECKSUM(NEWID()) % 3650), '1990-01-01') </code></pre> <p>My C# Code: </p> <pre><code> private void RunThis(string connString, StreamReader sr) { sr.BaseStream.Position = 0; string sqlQuery = sr.ReadToEnd(); using (SqlConnection connection = new SqlConnection(connString)) { Server server = new Server(new ServerConnection(connection)); server.ConnectionContext.StatementTimeout = 4200; server.ConnectionContext.ExecuteNonQuery(sqlQuery); } sr.Close(); } </code></pre> <p>........ </p> <pre><code> RunThis(e.Argument.ToString(), _updateClaim); </code></pre> <p>Where <code>e.Argument.ToString()</code> is the connection string.</p> <p>The <code>CREATE FUNCTION</code> scripts are run earlier, take very little time to run. Also, names are stored in tmp databases, these are entered in C# via arrays. These also take very little time to run.</p> <p>Table1 contains approx 140,000 rows and takes approx. 14 mins to complete.</p> <p>I have also tried using parameterised SQL queries, skipping the tmp tables and SQL functions and instead creating the SQL query and executing it from the code, such as the following:</p> <pre><code>UPDATE Table1 SET lastname = '{0}', firstname = '{1}', birthdate = DATEADD(DAY, ABS(CHECKSUM(NEWID()) % 3650), '1990-01-01'), address1 = '{2}', address2 = '{3}', address3 = '{4}' WHERE u_id = '{6}' </code></pre> <p>And some C#: </p> <pre><code> using (SqlConnection connection = new SqlConnection(connString)) { connection.Open(); for (int i = 0; i &lt; arraySize; ++i) { string updateString = string.Format(updateString2, GetRandomSurname(), GetRandomForeName(), GetRandomAddress1(), GetRandomAddress2(), GetRandomAddress3(), "", ids[i]); SqlCommand cmd = new SqlCommand(updateString, connection); cmd.CommandType = CommandType.Text; cmd.ExecuteNonQuery(); } } </code></pre> <p>The latter method also taking upwards of 14 minutes.</p> <p>Any ideas on how to cut down the time it takes to update the table?</p> <p>Thanks.</p>
 

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