Mar 10, 2021 · UNION ALL - Includes duplicates. UNION - Excludes duplicates. A UNION operation is different from a JOIN: A UNION concatenates result sets from two queries. But a UNION does not …

Sep 8, 2008 · The UNION ALL command is equal to the UNION command, except that UNION ALL selects all values. The difference between Union and Union all is that Union all will not eliminate …

May 25, 2009 · 76 UNION combines the results of two or more queries into a single result set that includes all the rows that belong to all queries in the union. By using JOINs, you can retrieve data …

Nov 30, 2022 · I've been trying to combine two tables into a temp table. My goal is to have the data of both tables available in one temp table I tried a couple of things: 1. SELECT * INTO #temp FROM …

Per the SQL Standard, the order of results is undefined barring an explicit order by clause. That first select in your example probably returns its results in the order returned by the subselect, but it is not …

You cannot use WITH in the middle of a query expression. WITH is used to build up intermediate queries for use by other queries immediately after (meaning it cannot be used by multiple …

Mar 27, 2011 · Basically, the UNION is looking for two complete SELECT statements to combine, and the WHERE clause is part of the SELECT statement. It may make more sense to apply the outer …

Mar 20, 2017 · I'm doing a UNION of two queries on an Oracle database. Both of them have a WHERE clause. Is there a difference in the performance if I do the WHERE after UNIONing the queries …

Mar 18, 2013 · SELECT * FROM (SELECT * FROM TABLE_A ORDER BY COLUMN_1)DUMMY_TABLE UNION ALL SELECT * FROM TABLE_B It results in the following …

I just read part of an optimization article and segfaulted on the following statement: When using SQL replace statements using OR with a UNION: select username from users where company = ‘bbc’ or