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Transcript
@@pack_received Number of input packets read by SQL Server since it was started. @@pack_sent Number of output packets sent by SQL Server since it was started. @@packet_errors Number of errors that have occurred since SQL Server was started. @@procid ID of the currently executing stored procedure. @@rowcount Number of rows affected by the last command. @@servername Name of the local SQL Server. @@spid Process ID number of the current process. @@sqlstatus Contains status information. @@textsize Maximum length of text or image data returned with SELECT statement. @@thresh_hysteresis Change in free space required to activate a threshold. @@timeticks Number of microseconds per tick. @@total_errors Number of errors that have occurred while reading or writing. @@total_read Number of disk reads since SQL Server was started. @@total_write Number of disk writes since SQL Server was started. @@tranchained Current transaction mode of the Transact-SQL program. @@trancount Nesting level of transactions. @@transtate Current state of a transaction after a statement executes. @@version Date of the current version of SQL Server. Using Variables The DECLARE keyword enables you to declare several variables with a single statement (although this device can sometimes look confusing when you look at your code later). An example of this type of statement appears here: 1> declare @batter_name char(30), @team int, @average float 2> go The next section explains how to use variables it to perform useful programming operations. Using Variables to Store Data Variables are available only within the current statement block. To execute a block of statements using the Transact-SQL language, the go statement is executed. (Oracle uses the semicolon for the same purpose.) The scope of a variable refers to the usage of the
