SQL Server/T-SQL/Table/TRUNCATE TABLE

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Timing the delete and truncate statements

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28> 29> create table employee( 30> ID int, 31> name nvarchar (10), 32> salary int, 33> start_date datetime, 34> city nvarchar (10), 35> region char (1)) 36> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> 3> 4> DECLARE @starttime DateTime 5> DECLARE @endtime DateTime 6> DECLARE @totaltime Int 7> 8> SET @starttime = GetDate() 9> DELETE FROM employee 10> SET @endtime = GetDate() 11> 12> SET @totaltime = DateDiff(ms, @starttime, @endtime) 13> PRINT "Time to Delete: " + CONVERT(VarChar(10), @totaltime) 14> 15> SET @starttime = GetDate() 16> TRUNCATE TABLE employee 17> SET @endtime = GetDate() 18> 19> SET @totaltime = DateDiff(ms, @starttime, @endtime) 20> PRINT "Time to Truncate: " + CONVERT(VarChar(10), @totaltime) 21> 22> drop table employee 23> GO (9 rows affected) (9 rows affected) Time to Delete: 13 (9 rows affected) Time to Truncate: 0 1> 2>

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TRUNCATE a TABLE

   <source lang="sql">

28> 29> create table employee( 30> ID int, 31> name nvarchar (10), 32> salary int, 33> start_date datetime, 34> city nvarchar (10), 35> region char (1)) 36> GO 1> 2> insert into employee (ID, name, salary, start_date, city, region) 3> values (1, "Jason", 40420, "02/01/94", "New York", "W") 4> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (2, "Robert",14420, "01/02/95", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (3, "Celia", 24020, "12/03/96", "Toronto", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (4, "Linda", 40620, "11/04/97", "New York", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (5, "David", 80026, "10/05/98", "Vancouver","W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (6, "James", 70060, "09/06/99", "Toronto", "N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (7, "Alison",90620, "08/07/00", "New York", "W") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (8, "Chris", 26020, "07/08/01", "Vancouver","N") 3> GO (1 rows affected) 1> insert into employee (ID, name, salary, start_date, city, region) 2> values (9, "Mary", 60020, "06/09/02", "Toronto", "W") 3> GO (1 rows affected) 1> 2> select * from employee 3> GO ID name salary start_date city region


---------- ----------- ----------------------- ---------- ------
         1 Jason            40420 1994-02-01 00:00:00.000 New York   W
         2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
         3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
         4 Linda            40620 1997-11-04 00:00:00.000 New York   N
         5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
         6 James            70060 1999-09-06 00:00:00.000 Toronto    N
         7 Alison           90620 2000-08-07 00:00:00.000 New York   W
         8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
         9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

(9 rows affected) 1> 2> 3> 4> DECLARE @starttime DateTime 5> DECLARE @endtime DateTime 6> DECLARE @totaltime Int 7> 8> SET @starttime = GetDate() 9> DELETE FROM employee 10> SET @endtime = GetDate() 11> 12> SET @totaltime = DateDiff(ms, @starttime, @endtime) 13> PRINT "Time to Delete: " + CONVERT(VarChar(10), @totaltime) 14> 15> SET @starttime = GetDate() 16> TRUNCATE TABLE employee 17> SET @endtime = GetDate() 18> 19> SET @totaltime = DateDiff(ms, @starttime, @endtime) 20> PRINT "Time to Truncate: " + CONVERT(VarChar(10), @totaltime) 21> 22> drop table employee 23> GO (9 rows affected) (9 rows affected) Time to Delete: 13 (9 rows affected) Time to Truncate: 0 1> 2>

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