Oracle distinct on one column

Nike, Adidas, Reebok, Asics. See the locations table in the sample database. DISTINCT treats NULL values to be duplicates of each other. The following will make all three columns distinct. I want only the Job_ID column to be distinct.

Note that only one of the rows above will be assigned ROW_NUMBER = , and it can be any of them. If this uncertainty is a problem, order by additional columns to get a clear winner. Oracle will decide, not you.

For this example, the highest pi. The query would return both rows because the ID column is different. I cannot get the distinct values of just one column using.

There have been numerous times I have wanted to do this, but have not found an easy way. In this instance I am selecting four columns and just want to distinct on the first column because the data of the four is different enough it returns duplicates of the first column. Well the title says it all. We can count distinct values such as in select count (distinct col1) from mytable;.

However when we do distinct on a column , that may have multiple nulls, it considers all nulls as 1. Ask Question Asked years, months ago. Max of CColumn record should be fine. I found an interesting non standard feature in postgres to distinguish one column in a query. How do I select distinct one column and return the other column data that has been distincted?

I need to select one of each version in the data (using the code field) while keeping all the columns in the final output. The issue is with this line. Hello, How to get distinct rows based on only one column ? I have tried distinct and group by but none of them working. How do you select multiple columns from a table while ensuring that one specific column doesnt contain duplicate values? This may be what you are looking for.

If you want to SUM one column based on the distinct values of another column , you may want to use a subquery to get the distinct values, and then perform a SUM. Now, we have only one NULL value included in the result set. I am wanting to display the commonName, scientificName, and planttype. Use column to specify one or more ordering columns. Rows with the same value for the first column are then sorted based on their values for the second column , and so on.

COUNT returns the number of rows returned by the query. The order_by_clause and windowing_clause are not allowed. I had a statement, built of two nested group by tables, and it hung.

This is support by the added functionality group by has - HAVING! Question: I need to display distinct records of each column within a single table. How do you write a SQL to select each distinct column within a table without using a function? Answer: By Laurent Schneider, from his book ? In this query we start by selecting the distinct values for all columns.

How do I see distinct values of more than one column in a single SQL command? Short questions are wonderful, because they leave more room for the answer. The state column has NULL values, meaning that the state data is not relevant to some cities e. Beijing, Hiroshima, and London.

If you only select one column , then it is OK, but if you want to select multiple columns based on a distinct value in one (or more) columns, test the and the response times thoroughly before you deploy this. Distinct will always force a sort that you may not need.