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UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
Selecting multiple columns in a pandas dataframe
...7 44
R3 47 30 84
R4 41 62 1
R5 5 58 0
...
Same works for selecting rows based on labels. Get the rows 'R6' to 'R10' from those columns:
df.loc['R6':'R10', 'C':'E']
Out:
C D E
R6 51 27 31
R7 83 19 18
R8 11 67 65
R9 78 27 29
R10 7 16 94
.loc also ac...
PostgreSQL array_agg order
...alues from a sorted subquery will usually work, however. For example:
SELECT xmlagg(x) FROM (SELECT x FROM test ORDER BY y DESC) AS tab;
So in your case you would write:
SELECT
array_to_string(array_agg(animal_name),';') animal_names,
array_to_string(array_agg(animal_type),';') animal_types
...
How can I selectively escape percent (%) in Python strings?
...
>>> test = "have it break."
>>> selectiveEscape = "Print percent %% in sentence and not %s" % test
>>> print selectiveEscape
Print percent % in sentence and not have it break.
...
Android Studio: Add jar as library?
.... Click the + sign above the panel second from the left -> Java
4.4. Select your local jar and add it to the project.
You may need to run the above ./gradlew command one more time
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imp...
Select elements by attribute
...
Do you mean can you select them? If so, then yes:
$(":checkbox[myattr]")
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Complex CSS selector for parent of active child [duplicate]
Is there a way to select a parent element based on the class of a child element in the class? The example that is relevant to me relating to HTML output by a nice menu plugin for http://drupal.org . The output renders like this:
...
Linq: GroupBy, Sum and Count
...a" is coming from, but the problem in the console app is that you're using SelectMany to look at each item in each group.
I think you just want:
List<ResultLine> result = Lines
.GroupBy(l => l.ProductCode)
.Select(cl => new ResultLine
{
ProductName =...
Explicitly select items from a list or tuple
...lution.I don't think it's a bad idea to invoke magic variable. programmer selects their preferred way based on programming circumstances.
– Jacob CUI
Mar 25 '15 at 22:57
add ...
String.Join method that ignores empty strings?
... simpler, since you can do it in SQL directly:
PostgreSQL & MySQL:
SELECT
concat_ws(' / '
, NULLIF(searchTerm1, '')
, NULLIF(searchTerm2, '')
, NULLIF(searchTerm3, '')
, NULLIF(searchTerm4, '')
) AS RPT_SearchTerms;
And even with the glorious MS-SQ...