Enable Trace Flags in SQL Server

This article on SQLServerCentral is sharing three ways to enabling trace flags behaviors in SQL server: at startup, with the QUERYTRACEON query hint, and with the DBCC TRACEON/TRACEOFF commands.
Per the MSDN website: "Trace flags are used to temporarily set specific server characteristics or to switch off a particular behavior. For example, if trace flag 3205 is set when an instance of SQL Server starts, hardware compression for tape drivers is disabled. Trace flags are frequently used to diagnose performance issues or to debug stored procedures or complex computer systems."