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Create a .txt file if doesn't exist, and if it does append a new line
... answered Jan 31 '18 at 19:38
R.ChaR.Cha
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Row Offset in SQL Server
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I would avoid using SELECT *. Specify columns you actually want even though it may be all of them.
SQL Server 2005+
SELECT col1, col2
FROM (
SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable...
How to split a String by space
...the trim caveat, you might want to consider the unicode non-breaking space character (U+00A0). This character prints just like a regular space in string, and often lurks in copy-pasted text from rich text editors or web pages. They are not handled by .trim() which tests for characters to remove usin...
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 ...
Equivalent of LIMIT and OFFSET for SQL Server?
...nation it's better to write a query like this:
;WITH Results_CTE AS
(
SELECT
Col1, Col2, ...,
ROW_NUMBER() OVER (ORDER BY SortCol1, SortCol2, ...) AS RowNum
FROM Table
WHERE <whatever>
)
SELECT *
FROM Results_CTE
WHERE RowNum >= @Offset
AND RowNum < @Offset +...
When should I use cross apply over inner join?
...APPLY works better on things that have no simple JOIN condition.
This one selects 3 last records from t2 for each record from t1:
SELECT t1.*, t2o.*
FROM t1
CROSS APPLY
(
SELECT TOP 3 *
FROM t2
WHERE t2.t1_id = t1.id
ORDER BY
t2.ran...
How to find gaps in sequential numbering in mysql?
...r
Here's version that works on table of any size (not just on 100 rows):
SELECT (t1.id + 1) as gap_starts_at,
(SELECT MIN(t3.id) -1 FROM arrc_vouchers t3 WHERE t3.id > t1.id) as gap_ends_at
FROM arrc_vouchers t1
WHERE NOT EXISTS (SELECT t2.id FROM arrc_vouchers t2 WHERE t2.id = t1.id + ...
Convert a list of characters into a string
If I have a list of chars:
9 Answers
9
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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
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Does a `+` in a URL scheme/host/path represent a space?
...ncoding in the path section of a URL is expected to be decoded, but
any + characters in the path component is expected to be treated literally.
To be explicit: + is only a special character in the query component.
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