the SELECT @@ the CONNECTIONS - Returns the number of connections since the last start or trying to connect. SELECT @@ CURSOR_ROWS - return connection (the number of rows to be returned valid data has not yet been opened cursor row read) the number of qualifying rows last open cursor currently exist SELECT @@ DATEFIRST - Back Weekly the first day figures the SELECT @@ eRROR - returns an error code of the last executed SQL statements. the SELECT @@ FETCH_STATUS - return status is the last cursor FETCH statement is executed, rather than the status of any currently open connections cursor. SELECT @@ the IDENTITY - returns the last inserted identity value, global SELECT the SCOPE_IDENTITY () - returns the last inserted identity value, the range of the SELECT @@ LANGID - returns the local language identifier currently used language (ID) . the SELECT @@ LANGUAGE - Returns the name of the language currently in use. SELECT @@ the LOCK_TIMEOUT - Returns the current lock current session timeout setting in milliseconds. SELECT @@ PROCID - Returns procedure stored identifier (ID) of the current process. the SELECT @@ ROWCOUNT - Returns the number of rows affected by the last statement. the SELECT @@ SERVERNAME - Returns the local name server is running. the SELECT @@ SPID - Returns the server process identifier (ID) of the current user process. the SELECT @@ TRANCOUNT - Returns the number of currently active connections affairs. the SELECT @@ VERSION - Returns the date, version and type of processor currently installed. the SELECT @@ CPU_BUSY - return since SQL Server last started working CPU time in milliseconds, the SELECT @@ DATEFIRST - Returns SET DATEFIRST command DATAFIRST parameter is assigned the value of SET DATEFIRST, command to specify the week The first day of the week the SELECT @@ DBTS - Returns the current timestamp value database must ensure the database timestamp value is only the SELECT @@ ERROR - returns an error code execute Transact-SQL statements in the SELECT @@ FETCH_STATUS - returns to the last FETCH statement the state values the SELECT @@ IDLE - return unit length of time since the last start SQL Server CPU is empty closed state of milliseconds the SELECT @@ io_busy - returns the CPU to perform input and output operations since the last time SQL Server starts spent time in milliseconds, to select @@ LANGID - returns the language ID value currently used in select @@ the lANGUAGE - returns the name of the currently used language select @@ the LOCK_TIMEOUT - returns the current session length of time waiting for a lock in milliseconds, select MAX_CONNECTIONS @@ - returns the maximum number of connections allowed to connect to SQL Server SELECT @@ MAX_PRECISION - Returns the data type of decimal and numeric precision SELECT @@ NESTLEVEL - Returns the stored procedure nesting level currently executed initial value 0 SELECT @@ the OPTIONS - returns the current option information SET SELECT @ @PACK_RECEIVED - returns the number of input packets read SQL Server via the network SELECT @@ pack_sent - returns the number of output packets addressed to SQL Server network SELECT @@ packet_errors - returns the number of errors in the packet network SELECT @@ PROCID - - returns the ID value currently stored procedure the SELECT @@ REMSERVER - returns the name of a remote SQL server database server, the SELECT @@ SERVICENAME -SQL Server is running to return to the state under which service the SQLServerAgent MSDTC as the MSSQLServer the SELECT @@ SPID - Returns the server process ID value of the current user process the SELECT @@ TEXTSIZE - return TEXTSIZE option values SET statement SET statement defines the SELECT statement the maximum length of the basic units of text or image data type byte SELECT @@ TimeTicks - returns the number of microseconds each clock SELECT @@ total_errors - returns the number of disk read and write error SELECT @@ total_read - returns the disk read operation the number of the SELECT @@ TOTAL_WRITE - returns the number of disk writes the SELECT @@ TRANCOUNT - returns the current connection is active in number of transactions
- the same point: identity value is returned last inserted - differences: - @@ Identity: Returns the last session identifier value, is not limited to a specific scope; - IDENT_CURRENT ( 'TableName'): return any Finally, a session identification value of the specified table, any scope of generated; - SCOPE_IDENTITY: returns the current session identifier value of the current scope of any last generated table.
