title: What are the differents between USE | select_db function or TABLENAME.dbo?
body: <p>I'm using mssql and PHP and I wanna know what are the differents <br>between changing database with the function mssql_change_db, or to add USE [DB_NAME] in the start of the query or to add DB_NAME.dbo.tablename in every query? <Br>
  For example, I have database named "LogsDB" <br>
  So, what's the better way to execute query with database switching. <br>
  <hr>
  Like this? : <br></p>
  
  <pre><code>mssql_select_db("LogsDB", $this -&gt; sqlHandle);
  mssql_query("select top 1 username from changePW");
  </code></pre>
  
  <p><hr>
  Or like this? : <br></p>
  
  <pre><code>mssql_query("USE [LogsDB] select top 1 username from changePW");
  </code></pre>
  
  <p><hr>
  Or like this? : <br>
  <code>mssql_query("select top 1 username from LogsDB.dbo.changePW");</code> <br>
  In this way, the database will be changed only for this query, and it's nice. <br>
  Is there another way to set database not to change but to execute query to it?
  <hr>
  If there are more ways to switch databases, and they are better than what I said here, I'll be happy to hear about them.<br>
  Thanks in advance :)</p>