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AI2 Keep Awake
... Notice: The lifespan of the device battery will be significantly reduced by using this extension. Do not set WakeLocks if you do not really need them, use them as rarely as possible and release them as soon as possible. If actions are to be performed only occasionally, it is not necessary f...
mysql query order by multiple items
is is possible to order by multiple rows?
3 Answers
3
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What is the simplest SQL Query to find the second largest value?
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Much better than my approach using ORDER_BY and LIMIT for the inner statement
– andig
Oct 8 '15 at 9:58
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How to use Oracle ORDER BY and ROWNUM correctly?
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The where statement gets executed before the order by. So, your desired query is saying "take the first row and then order it by t_stamp desc". And that is not what you intend.
The subquery method is the proper method for doing this in Oracle.
If you want a version that w...
How to select only the first rows for each unique value of a column
...ddress 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
CName, MIN(Inserted) AS First
FROM
MyTable...
mysql error 1364 Field doesn't have a default values
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Set a default value for Created_By (eg: empty VARCHAR) and the trigger will update the value anyways.
create table try (
name varchar(8),
CREATED_BY varchar(40) DEFAULT '' not null
);
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How does PHP 'foreach' actually work?
Let me prefix this by saying that I know what foreach is, does and how to use it. This question concerns how it works under the bonnet, and I don't want any answers along the lines of "this is how you loop an array with foreach ".
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Applying a function to every row of a table using dplyr?
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You need to group by row:
iris %>% group_by(1:n()) %>% mutate(Max.Len= max(Sepal.Length,Petal.Length))
This is what the 1 did in adply.
share
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PostgreSQL Crosstab Query
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FROM crosstab(
'SELECT section, status, ct
FROM tbl
ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here
) AS ct ("Section" text, "Active" int, "Inactive" int);
Returns:
Section | Active | Inactive
---------+--------+----------
A | 1 | 2
B | 4 | ...
What is meant by the term “hook” in programming?
...ay be able to hook into the interrupt handling process though, for example by modifiying the table listing the locations of the interrupt handlers so that your code gets called first on interrupt (and then your code would call the previously present interrupt handling code, in a daisy-chain manner)
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