How to select unique records by SQL - Stack Overflow
DISTINCT works to select a distinct combination of all the columns you selected. In this case, the combination "item1,data1" and "item1,data2" are two completely different combinations of the two …
How do I (or can I) SELECT DISTINCT on multiple columns?
Sep 10, 2008 · The problem with your query is that when using a GROUP BY clause (which you essentially do by using distinct) you can only use columns that you group by or aggregate functions.
sql - DISTINCT e GROUP BY, qual a diferença entre ambas as …
Aug 11, 2017 · DISTINCT A instrução SELECT DISTINCT é usada para retornar apenas valores distintos (diferentes). Dentro de uma tabela, uma coluna geralmente contém muitos valores …
MySQL: Select DISTINCT / UNIQUE, but return all columns?
May 25, 2011 · SELECT DISTINCT FIELD1, FIELD2, FIELD3 FROM TABLE1 works if the values of all three columns are unique in the table. If, for example, you have multiple identical values for first …
sql - Using DISTINCT and TOP in the same query - Stack Overflow
I want to use DISTINCT and TOP in the same query. I tried SELECT DISTINCT TOP 10 * FROM TableA but I still have a duplicate personID, so I tought to do: SELECT DISTINCT (personID) TOP 10 * …
sql - DISTINCT for only one column - Stack Overflow
Feb 19, 2017 · SELECT DISTINCT TOP 1 ID, Email, ProductName, ProductModel FROM Products ORDER BY ID DESC The TOP 1 will return only the first record, by ordering it by the ID descending …
sql - How to use DISTINCT and ORDER BY in same SELECT statement ...
SELECT Category i.e. remove the extended sort key column again from the result. So, thanks to the SQL standard extended sort key column feature, it is totally possible to order by something that is not …
SQL to find the number of distinct values in a column
Apr 5, 2019 · SELECT COUNT(DISTINCT column_name) AS some_alias FROM table_name This will count only the distinct values for that column.
sql - Counting DISTINCT over multiple columns - Stack Overflow
Sep 24, 2009 · SELECT COUNT(*) FROM (SELECT DISTINCT DocumentId, DocumentSessionId FROM DocumentOutputItems) AS internalQuery I need to count the number of distinct items from …
sql - Difference between Select Unique and Select Distinct - Stack …
Dec 3, 2008 · Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than Oracle, SELECT UNIQUE may not be recognized at all.