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SQL select join: is it possible to prefix all columns as 'prefix.*'?

... if this is possible in SQL. Say you have two tables A and B, and you do a select on table A and join on table B: 22 Answer...
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Find rows with multiple duplicate fields with Active Record, Rails & Postgres

... Tested & Working Version User.select(:first,:email).group(:first,:email).having("count(*) > 1") Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the end: User.select(:first,:email).gro...
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How to use GROUP_CONCAT in a CONCAT in MySQL

... select id, group_concat(`Name` separator ',') as `ColumnName` from ( select id, concat(`Name`, ':', group_concat(`Value` separator ',')) as `Name` from mytbl group by id, `Name` ) tbl group by id; ...
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How do I put an 'if clause' in an SQL string?

... WHERE purchaseOrder_ID = '@purchaseOrder_ID' and not exists (SELECT * FROM itemsOrdered WHERE purchaseOrder_ID = '@purchaseOrdered_ID' AND status = 'PENDING' ) However, I might guess that you are looping at a higher level. To set all such v...
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Check if a temporary table exists and delete if it exists before creating a temporary table

...me in SQL Server 2005, with the extra "foo" column appearing in the second select result: IF OBJECT_ID('tempdb..#Results') IS NOT NULL DROP TABLE #Results GO CREATE TABLE #Results ( Company CHAR(3), StepId TINYINT, FieldId TINYINT ) GO select company, stepid, fieldid from #Results GO ALTER TABLE #R...
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MySQL combine two columns into one column

...does not start with a digit, then the converted value is 0. So try this: select concat(column1, column2) Two ways to add a space: select concat(column1, ' ', column2) select concat_ws(' ', column1, column2) share ...
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Cast int to varchar

...datatype, there is no varchar datatype that you can cast/convert data to: select CAST(id as CHAR(50)) as col1 from t9; select CONVERT(id, CHAR(50)) as colI1 from t9; See the following SQL — in action — over at SQL Fiddle: /*! Build Schema */ create table t9 (id INT, name VARCHAR(55)); ins...
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How to auto-indent code in the Atom editor?

...auto-indent your code in the Atom editor? In other editors you can usually select some code and auto-indent it. 11 Answers...
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SQL variable to hold list of integers

...e @listOfIDs table (id int); insert @listOfIDs(id) values(1),(2),(3); select * from TabA where TabA.ID in (select id from @listOfIDs) or declare @listOfIDs varchar(1000); SET @listOfIDs = ',1,2,3,'; --in this solution need put coma on begin and end select * from TabA where charindex(',' + C...
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tmux set -g mouse-mode on doesn't work

...n. There's now no longer options for: - mouse-resize-pane - mouse-select-pane - mouse-select-window - mode-mouse Instead there is just one option: 'mouse' which turns on mouse support So this is what I'm using now in my .tmux.conf file set -g mouse on ...