Hi, I create a table as follows:
CREATE TABLE MyTable (F1 INTEGER, F2 INTEGER); Then add the following records: INSERT INTO MyTable (F1, F2) Values (1, 2); INSERT INTO MyTable (F1, F2) Values (1, 3); INSERT INTO MyTable (F1, F2) Values (2, 4); INSERT INTO MyTable (F1, F2) Values (2, 5); INSERT INTO MyTable (F1, F2) Values (3, 6); INSERT INTO MyTable (F1, F2) Values (3, 7); INSERT INTO MyTable (F1, F2) Values (4, 2); Then I want to obtain the total count of unique values for F1 field. In the above sample, since unique F1 field values are 1, 2, 3 and 4, so the count is 4. How to write SQL query to obtain the value? Thanks
