Difficulty in understanding sql syntax

[AtomicWedgie]

Hi,

I have some SQL statements that were developped by someone else and I am having a very hard time in understanding what the syntax does. Could anybody enlighten me?


UPDATE Table_X
SET Field1 = (SELECT avg(FIELD1)
FROM Table_B
WHERE Table_A.FIELD2 = Table_B.FIELD2)
FROM Table_X Table_A
WHERE Table_A.Field3 = 'yyyy'


Regards,

AtomicWedgie

 

[jbenson001]

Field1 in TableX is being updated with the Average of Field1 in TableB where Field2 in TableA(alias for TableX) = Field2 in TableB

And that UPDATE is only being done on rows in Table_X where Field3 = 'yyyy'


Jim