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What is the purpose of Order By 1 in SQL select statement?
...number stands for the column based on the number of columns defined in the SELECT clause. In the query you provided, it means:
ORDER BY A.PAYMENT_DATE
It's not a recommended practice, because:
It's not obvious/explicit
If the column order changes, the query is still valid so you risk ordering ...
How to use OpenFileDialog to select a folder?
How to use OpenFileDialog to select folders?
8 Answers
8
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How to send data to local clipboard from a remote SSH session
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I often to this in vim. To do so, select what you want to copy in visual mode, then type: :'<,'>w !ssh desktop pbcopy
– Mike Brennan
Nov 30 '12 at 5:04
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Copying text outside of Vim with set mouse=a enabled
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Press shift while selecting with the mouse. This will make mouse selection behave as if mouse=a was not enabled.
Note: this trick also applies to "middle button paste": if you want to paste in vim text that was selected outside, press shift w...
How do I use variables in Oracle SQL Developer?
... other stuff didn't work for me, but this did:
define value1 = 'sysdate'
SELECT &&value1 from dual;
Also it's the slickest way presented here, yet.
(If you omit the "define"-part you'll be prompted for that value)
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Entity Framework select distinct name
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Using lambda expression..
var result = EFContext.TestAddresses.Select(m => m.Name).Distinct();
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Select rows which are not present in other table
...task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM login_log l
WHERE NOT EXISTS (
SELECT -- SELECT list mostly irrelevant; can just be empty in Postgres
FROM ip_location
WHERE ip = l.ip
);
Also consider:
What is easier to read in EXISTS...
UITableView Setting some cells as “unselectable”
How can I set the UITableView's cell property to be unselectable? I don't want to see that blue selection box when the user taps on the cell.
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How to select only the first rows for each unique value of a column
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A very simple answer if you say you don't care which address is used.
SELECT
CName, MIN(AddressLine)
FROM
MyTable
GROUP BY
CName
If you want the first according to, say, an "inserted" column then it's a different query
SELECT
M.CName, M.AddressLine,
FROM
(
SELECT
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SQL “select where not in subquery” returns no results
...MySQL
There are three ways to do such a query:
LEFT JOIN / IS NULL:
SELECT *
FROM common
LEFT JOIN
table1 t1
ON t1.common_id = common.common_id
WHERE t1.common_id IS NULL
NOT EXISTS:
SELECT *
FROM common
WHERE NOT EXISTS
(
SELECT NULL
FROM ...