Updating only non-null fields in join

[RyanProbyn]

Hi,

I have a table which i want to update the value of using another table, only if the value from the table is not null.

example:

Table 1:

ID	type
1	a
2	b
3	c

Table 2:

ID	type
1	NULL
2	d
3	e

joining the tables should give:

ID	type
1	a
2	d
3	e

Kind regards,

Ryan

[lironbaram]

hi,
this script should work for you 

Table2:
NoConcatenate load * Inline [
ID,	type
1,NULL
2,d
3,e
]; 
updateType:
mapping load * Resident Table2 where type<>'NULL';

drop table Table2;

Data:
load ID,
     type as OldType,
     ApplyMap('updateType',ID,type) as type;
load * inline [ 
ID,type
1,a
2,b
3,c];

[RyanProbyn]

Hi,

Thank you for your response but unfortunately the suggestion didn't quite work with my data.

I ended up joining my two tables on ID and with differently named type columns. then reloading as follows:

Final_Table:
Load id,
if(isnull(Type_Table_2), Type, Type_Table_2) as Type
Resident Table_1_2_joined;

Kind regards,

Ryan