SQL-根据另一列的值选择与另一列不同的值

Question

I am looking to run a SQL query that counts the distinct values from one column based on the value of another column being equal to X.

So for the below, I want to count the distinct values of the "value" column where the "field_number" column is equal to 2.

The result should return "2" (Australia and New Zealand)

Answer 1

select count(distinct value)
from your_table
where field_number = 2

Answer 2

You can use the below query

select count(distinct value) from my_table where field_number = 2;

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