How to Obtain Multiple Counts With a Single Query in PL/SQ

How to Obtain Multiple Counts With a Single Query in PL/SQ

To obtain multiple counts with a single query in PL/SQL, you can use either conditional aggregation or multiple subqueries. Conditional aggregation involves using the SUM() function with CASE statements to count rows based on specific conditions. Multiple subqueries employ separate SELECT statements within the main query to count rows for each condition. Each approach has its advantages and is suited to different requirements....

Let’s Setup an Environment

Let’s create an ”employeeDetails” and insert the value in it:...

1. Using Conditional Aggregation

The SUM() function is used with conditional expressions so that we count rows based on different-different conditions. Now the CASE statement evaluate each row against the specified condition, add 1 to the count if true otherwise 0 if false....

2. Using Multiple Subqueries

Using multiple subqueries in PL/SQL enables counting rows based on different conditions within a single query. Each subquery retrieves counts for specific conditions, allowing for a comprehensive analysis of the data. This approach provides flexibility in counting rows based on various criteria without needing multiple separate queries....

Conclusion

In conclusion, both conditional aggregation and multiple subqueries offer effective ways to obtain multiple counts with a single query in PL/SQL. While conditional aggregation simplifies the process with concise syntax, multiple subqueries provide flexibility for complex counting scenarios. Choosing the method depends on the specific requirements of the analysis....