How do I get distinct columns in SQL?

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How do I distinct all columns in SQL?

The DISTINCT keyword is applied to all columns. It means that the query will use the combination of values in all columns to evaluate the distinction. If you want to select distinct values of some columns in the select list, you should use the GROUP BY clause.

How do I get two distinct columns in SQL?

DISTINCT on multiple columns

Sample Select statement.
Select with distinct on two columns.
Select with distinct on three columns.
Select with distinct on all columns of the first query.
Select with distinct on multiple columns and order by clause.
Count() function and select with distinct on multiple columns.

How do I select all columns with distinct?

The correct answer is to use a GROUP BY on the columns that you want to have unique answers: SELECT col1, col2 FROM mytable GROUP BY col2 will give you arbitrary unique col2 rows, with their col1 data as well.

How can I get distinct count of multiple columns in SQL?

SQL databases can work with tuples like values so you can just do: SELECT COUNT(DISTINCT (DocumentId, DocumentSessionId)) FROM DocumentOutputItems; If your database doesn’t support this, it can be simulated as per @oncel-umut-turer’s suggestion of CHECKSUM or other scalar function providing good uniqueness e.g. COUNT( …

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Does distinct work on all columns?

Yes, DISTINCT works on all combinations of column values for all columns in the SELECT clause.

Can we apply distinct on multiple columns?

Yes, the DISTINCT clause can be applied to any valid SELECT query. It is important to note that DISTINCT will filter out all rows that are not unique in terms of all selected columns.

What is difference between unique and distinct?

The main difference between unique and distinct is that UNIQUE is a constraint that is used on the input of data and ensures data integrity. While DISTINCT keyword is used when we want to query our results or in other words, output the data.

How do I get distinct to only one column?

Adding the DISTINCT keyword to a SELECT query causes it to return only unique values for the specified column list so that duplicate rows are removed from the result set. Since DISTINCT operates on all of the fields in SELECT’s column list, it can’t be applied to an individual field that are part of a larger group.

How do you eliminate duplicate rows in SQL query without distinct?

Below are alternate solutions :

Remove Duplicates Using Row_Number. WITH CTE (Col1, Col2, Col3, DuplicateCount) AS ( SELECT Col1, Col2, Col3, ROW_NUMBER() OVER(PARTITION BY Col1, Col2, Col3 ORDER BY Col1) AS DuplicateCount FROM MyTable ) SELECT * from CTE Where DuplicateCount = 1.
Remove Duplicates using group By.

How do you select distinct records?

SQL SELECT DISTINCT Explanation

SELECT DISTINCT returns only unique (i.e. distinct) values. SELECT DISTINCT eliminates duplicate values from the results. DISTINCT can be used with aggregates: COUNT, AVG, MAX, etc. DISTINCT operates on a single column.

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How does select distinct work?

When only one expression is provided in the DISTINCT clause, the query will return the unique values for that expression. When more than one expression is provided in the DISTINCT clause, the query will retrieve unique combinations for the expressions listed. In SQL, the DISTINCT clause doesn’t ignore NULL values.

How do I count different columns on the same table?

SELECT CompanyName, TotalOpenClaims = COUNT(CASE WHEN StatusID = 1 THEN ClaimID END), TotalClosedClaims = COUNT(CASE WHEN StatusID = 2 THEN ClaimID END), TotalReOpenedClaims = COUNT(CASE WHEN StatusID = 3 THEN ClaimID END), TotalPendingClaims = COUNT(CASE WHEN StatusID = 4 THEN ClaimID END) FROM dbo.