Question

I have the following TSQL codes:

-- 1. define a cursor DECLARE c_Temp CURSOR FOR     SELECT name FROM employees;  DECLARE @name varchar(100); -- 2. open it OPEN c_Temp; -- 3. first fetch FETCH NEXT FROM c_Temp INTO @name; WHILE @@FETCH_STATUS = 0 BEGIN   print @name;   FETCH NEXT FROM c_Temp INTO @name; -- fetch again in a loop END -- 4. close it .... 

I use the name value only in a loop block. Here I have to

1. define a cursor variable,
2. open it,
3. fetch twice and
4. close it.

In PL/SQL, the loop can be like this:

FOR rRec IN (SELECT name FROM employees) LOOP   DBMS_OUTPUT.put_line(rRec.name); END LOOP; 

It is much simpler than my TSQL codes. No need to define a cursor. It is created dynamically which is accessible within a loop block (much like C# for loop). Not sure if there something similar like this in TSQL?

Answer 1

Cursors are evil in Sql Server as they can really degrade performance – my favoured approach is to use a Table Variable (>= Sql Server 2005) with an auto inc ID column:

Declare @LoopTable as table (      ID int identity(1,1),      column1 varchar(10),      column2 datetime ) insert into @LoopTable (column1, column2) select name, startdate from employees  declare @count int declare @max int select @max = max(ID) from @LoopTable  select @count = 1  while @count <= @max begin    --do something here using row number '@count' from @looptable    set @count = @count + 1 end 

It looks pretty long winded however works in any situation and should be far more lightweight than a cursor