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How can I disable the UITableView selection?
When you tap a row in a UITableView , the row is highlighted and selected. Is it possible to disable this so tapping a row does nothing?
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ROW_NUMBER() in MySQL
...asy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.col1 AND t0.col2=t1.col2 AND t1.col3>t0.col3
WHERE t1.col1 IS NULL;
“Get the rows in the table for which no other row with matching col1,col2 has a hi...
Why is division in Ruby returning an integer instead of decimal value?
...t; 1.8
This also works if your values are variables instead of literals. Converting one value to a float is sufficient to coerce the whole expression to floating point arithmetic.
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Select where count of one field is greater than one
...clause, for aggregate result comparison.
Taking the query at face value:
SELECT *
FROM db.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparati...
How to use `string.startsWith()` method ignoring the case?
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One option is to convert both of them to either lowercase or uppercase:
"Session".toLowerCase().startsWith("sEsSi".toLowerCase());
This is wrong. See: https://stackoverflow.com/a/15518878/14731
Another option is to use String#regionMat...
Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...
SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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How do I make a Git commit in the past?
I'm converting everything over to Git for my own personal use and I found some old versions of a file already in the repository. How do I commit it to the history in the correct order according the file's "date modified" so I have an accurate history of the file?
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How do I do top 1 in Oracle?
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If you want just a first selected row, you can:
select fname from MyTbl where rownum = 1
You can also use analytic functions to order and take the top x:
select max(fname) over (rank() order by some_factor) from MyTbl
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how to listen to N channels? (dynamic select statement)
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You can do this using the Select function from the reflect package:
func Select(cases []SelectCase) (chosen int, recv Value, recvOK bool)
Select executes a select operation described by the list of cases. Like
the Go select statement, it bl...