Executing SQL query based on certain condition

[Harish V Gupta]

I want to get data from a table based on certain condition. For eg, if table1 is not empty then get complete data from table2 else get the data from table2 for which created_dt (let's say it's one of the columns in table2) is today's date. It's like following :

if(condition)
then execute query1
else
execute query2

Is there any way to achieve this in SQL?

[James Peterson]

Hi Harish V Gupta,

You can use count(*) method to know the number of rows depending on that result you can write the query.

Regardss,
James

[Harish V Gupta]

Thanks for the reply James. You are right that count(*) will give me total number of records. But I am not able to figure out how to use that value in a condition for choosing between queries.

[T Mishra]

If I understand correctly, I think you are trying to evaluate condition at the database layer. Isn't the condition a part of business layer ? The job of the lowest layer of ORM must be to execute a query. Which query has to be executed must be decided at the business layer. In short, you can use count(*) to evaluate the ccondition and use the ORM to execute the query.