oracle - Query in WHEN NO_DATA_FOUND clause. Bad practice? -

developers @ our job using follow construct:

begin       select field1    l_field1   table1   field2 = 'some value' exception   when no_data_found        select field2       l_field2      table2      field3 = 'some value'    ... end; 

what means - if don't find record in first table go in second table.

i have strong feeling wrong , bad lazy practice. how approach it? first count in table1 , if number of rows 0 go , in table2?

if asking alternative way, can use below way. when no data found considered handle errors or warning, , not conditions. exceptions helps handle errors , if trying run several selects , had error .the exception detect check below example.

begin    declare cnt number(4);  select count(1) cnt table1 field2 = 'some value'; if cnt >0   select field1    l_field1   table1   field2 = 'some value' else if cnt =0   select field2       l_field2      table2      field3 = 'some value'; end if;    end; 

with exceptions, can handle errors conveniently without need code multiple checks, follows:

begin    select ...    select ...    select ...    ... exception    when no_data_found  -- catches 'no data found' errors 

for more information exception , handling errors check oracle documentation