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Hello All,
I am working on an application which was already developed by someone else. I came across one of the joins condition "Add Left Join", at first I thought it must be "Add Load', but it seems that it is "Add Left Join", I would like to know if it exists or not before going into a discussion with the concerned people. If that particular condition exists can anyone please explain it's working.
Thanks in advance.
 Peter_Cammaert
		
			Peter_Cammaert
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		Yes they are equivalent.
ADD, LEFT and JOIN(tablename) are all LOAD statement prefixes. The order in which you specify them is not important. As prefixes generally do, they should be placed before the LOAD keyword.
 vikasmahajan
		
			vikasmahajan
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		TableA :
load * from Sales
left join (TableA)
load * from orders
where condition ;
HTH
Vikas
 
					
				
		
 sujeetsingh
		
			sujeetsingh
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		Use left join simple.
 
					
				
		
 avinashelite
		
			avinashelite
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		Is it a comment like Add left join or its a script statement ??
could you please share the script ? so that we can try to identify how its used in the script ??
 
					
				
		
 avinashelite
		
			avinashelite
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		I feel they have written it for the Partial reload purpose ...
i.e if you click on the partial reload option from the file menu only the table with the Add left join will get loaded and the other statements will be ignored
Hope this helps you
 Peter_Cammaert
		
			Peter_Cammaert
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		Indeed. The ADD prefix doesn't do anything during a normal script run. However it kicks into action when performing a Partial Reload. ADD tries to load data without first removing the target table. Sort of a switchable CONCATENATE LOAD. Compare this to its counterpart REPLACE which will effectively drop the existing target table during a partial reload, before loading new rows.
Not sure whether this can be sensibly combined with a LEFT JOIN though... Does it work?
 
					
				
		
 avinashelite
		
			avinashelite
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		Hi pcammaert , yes its works fine with the left join . Just now I tested with same data it works fine 
 
					
				
		
Hi Avinash,
Thanks for the quick response. So according to what you say
Add Left join
Load * from..............
and
Left Join
Add Load * from .................
are the same right?
 
					
				
		
 avinashelite
		
			avinashelite
		
		
		
		
		
		
		
		
	
			
		
		
			
					
		If you go for normal reload then both are same ...both the statements will execute  but if go for Partial reload then only the
 but if go for Partial reload then only the 
Add Left join
Load * from..............
will get executed and rest of the statements will retain the old data
 
					
				
		
If we do a partial reload according to my knowledge, only the tables with Add or Replace prefixes will execute ignoring all the other tables. So here will the both Loads execute and return the same output?
