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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.
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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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What is the difference between HAVING and WHERE in SQL?
...his code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities...
How to define a custom ORDER BY order in mySQL
...ndy function called FIELD() which is excellent for tasks like this.
ORDER BY FIELD(Language,'ENU','JPN','DAN'), ID
Note however, that
It makes your SQL less portable, as other DBMSs might not have such function
When your list of languages (or other values to sort by) gets much longer, it's bette...
Clear text from textarea with selenium
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driver.find_element_by_id('foo').clear()
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