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SQL Query to concatenate column values from multiple rows in Oracle
...on on string aggregation techniques. A very common one is to use LISTAGG:
SELECT pid, LISTAGG(Desc, ' ') WITHIN GROUP (ORDER BY seq) AS description
FROM B GROUP BY pid;
Then join to A to pick out the pids you want.
Note: Out of the box, LISTAGG only works correctly with VARCHAR2 columns.
...
Random record in ActiveRecord
...he first, all after are still sorted by id). If you need multiple randomly selected records you must use this approach multiple times or use the random order method provided by your database, i.e. Thing.order("RANDOM()").limit(100) for 100 randomly selected entries. (Be aware that it's RANDOM() in P...
SQL Server Output Clause into a scalar variable
...
But then I'd have to "SELECT @someInt = ID FROM @ID". I wanted to know if its possible to skip that extra step (and intermediary table variable) if all I need is the resulting int.
– Benoittr
Apr 5 '11 at 21:...
SQL: How to perform string does not equal
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Try the following query
select * from table
where NOT (tester = 'username')
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How to trim a string in SQL Server before 2017?
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SELECT LTRIM(RTRIM(Names)) AS Names FROM Customer
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How do I use jQuery's form.serialize but exclude empty fields
... looking over the jQuery docs and I think we can do this in one line using selectors:
$("#myForm :input[value!='']").serialize() // does the job!
Obviously #myForm gets the element with id "myForm" but what was less obvious to me at first was that the space character is needed between #myForm and...
NOT IN vs NOT EXISTS
...llow NULLs the NOT IN will be treated identically to the following query.
SELECT ProductID,
ProductName
FROM Products p
WHERE NOT EXISTS (SELECT *
FROM [Order Details] od
WHERE p.ProductId = od.ProductId)
The exact plan may vary but for my examp...
What is the difference between single and double quotes in SQL?
...ould be more readable as product_id, so you use either of the following:
SELECT PRODUCT.id AS product_id
SELECT PRODUCT.id 'product_id'
Either works in Oracle, SQL Server, MySQL… but I know some have said that the TOAD IDE seems to give some grief when using the single quotes approach.
You do...
Is there a way to access the “previous row” value in a SELECT statement?
...d to order by some column for this to be meaningful. Something like this:
select t1.value - t2.value from table t1, table t2
where t1.primaryKey = t2.primaryKey - 1
If you know how to order things but not how to get the previous value given the current one (EG, you want to order alphabetically) ...
IntelliJ: Working on multiple projects
...ven Projects" window (View > Tool Windows > Maven Projects) and then select the additional pom file you want to import.
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