EXCEPT
combines the result sets of two or more tables and retrieves rows specific to the first SELECT
statement but not present in the subsequent ones.
EXCEPT
is as follows:
value1, value2, ... value_n
: The columns you want to retrieve.table1, table2
: The tables from which you wish to retrieve records.vehicles
and vehicles1
. You want to find the vehicle which was present in 2021 but is not present in 2022:
EXCEPT
to find employees present in 2021 but not in 2022:
vehicles
) but not found in the second table (vehicles1
). In this case, the result is the vehicle name “Truck.”
EXCEPT ALL
allows you to find rows specific to the first SELECT
statement while preserving duplicate entries.
EXCEPT ALL
is similar to EXCEPT
:
value1, value2, ... value_n
: The columns you want to retrieve.table1, table2
: The tables from which you wish to retrieve records.SELECT
queries must be compatible.EXCEPT ALL
to find customers who have purchased products from one marketplace but not from the other:
customer_id
who has only transacted in the first marketplace and has not engaged in any corresponding transactions in the second marketplace.
marketplace1_transactions
) but missing in the second marketplace (marketplace2_transactions
).
left_array_values
and right_array_values
, to hold sets of values.
EXCEPT ALL
operation to compare the values within the arrays, focusing on unique elements while retaining duplicate entries.
EXCEPT ALL
operation processes each element individually from both inputs at a time. The comparison occurs element-wise, leading to the inclusion of both 1 and 3 in the final result.