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SQL - using alias in Group By
... following order:
FROM clause
WHERE clause
GROUP BY clause
HAVING clause
SELECT clause
ORDER BY clause
For most relational database systems, this order explains which names (columns or aliases) are valid because they must have been introduced in a previous step.
So in Oracle and SQL Server, you...
How to use GROUP BY to concatenate strings in SQL Server?
...S (1,'B',8)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (2,'C',9)
SELECT
[ID],
STUFF((
SELECT ', ' + [Name] + ':' + CAST([Value] AS VARCHAR(MAX))
FROM #YourTable
WHERE (ID = Results.ID)
FOR XML PATH(''),TYPE).value('(./text())[1]','VARCHAR(MAX)')
,1,2,'') AS NameVa...
How do I make a placeholder for a 'select' box?
...s which is working out just fine. But I'd like to use a placeholder for my selectboxes as well. Of course I can just use this code:
...
Copy data into another table
...
If both tables are truly the same schema:
INSERT INTO newTable
SELECT * FROM oldTable
Otherwise, you'll have to specify the column names (the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema)...
Find rows that have the same value on a column in MySQL
...sses and how many times they're used, with the most used addresses first.
SELECT email,
count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC
If you want the full rows:
select * from table where email in (
select email from table
group by email having count(*) &g...
Detect if value is number in MySQL
...
This should work in most cases.
SELECT * FROM myTable WHERE concat('',col1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
share
...
How to automatically select all text on focus in WPF TextBox?
If I call SelectAll from a GotFocus event handler, it doesn't work with the mouse - the selection disappears as soon as mouse is released.
...
How do I split a string so I can access item x?
...0,
PATINDEX('%|%', @products))
SELECT @individual
SET @products = SUBSTRING(@products,
LEN(@individual + '|') + 1,
LEN(@products))
END
ELSE
BEGIN
SET @individu...
SELECT INTO Variable in MySQL DECLARE causes syntax error?
I´d like to SELECT a single value into a variable. I´d tried to following:
11 Answers
...
Difference between “read commited” and “repeatable read”
...nd consider you have a simple task like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any da...