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Is there a common Java utility to break a list into batches?
...
Another approach is to use Collectors.groupingBy of indices and then map the grouped indices to the actual elements:
final List<Integer> numbers = range(1, 12)
.boxed()
.collect(toList());
System.out.println(numbers);
fi...
postgresql COUNT(DISTINCT …) very slow
...ZE
SELECT
COUNT (distinct val) as aantal
FROM one
;
\echo group by+count(*)
EXPLAIN ANALYZE
SELECT
distinct val
-- , COUNT(*)
FROM one
GROUP BY val;
\echo with CTE
EXPLAIN ANALYZE
WITH agg AS (
SELECT distinct val
FROM one
GROUP BY val
)
SELECT COUNT ...
Give all the permissions to a user on a DB
...e following:
GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA MY_SCHEMA TO MY_GROUP;
GRANT ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA MY_SCHEMA TO MY_GROUP;
If you want to enable this for newly created relations too, then set the default permissions:
ALTER DEFAULT PRIVILEGES IN SCHEMA MY_SCHEMA
GRA...
How can I run just the statement my cursor is on in SQL Server Management Studio?
...y executes the whole script. I wanted to search for it in the user support group (toadss(at)yahoogroups.com) but yahoo has the stupidest search facility ever! It can't even find the keyword "toad" in the toad mail group, DOH!
I think TOAD is the best querying tool ever, but the lack of this featur...
How do I see active SQL Server connections?
... loginame as LoginName
FROM
sys.sysprocesses
WHERE
dbid > 0
GROUP BY
dbid, loginame
;
See also the Microsoft documentation for sys.sysprocesses.
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Regex select all text between tags
...re>", (replacing pre with whatever text you want) and extract the first group (for more specific instructions specify a language) but this assumes the simplistic notion that you have very simple and valid HTML.
As other commenters have suggested, if you're doing something complex, use a HTML par...
What is the difference between RegExp’s exec() function and String’s match() function?
...o more matches.
String.match does this for you and discards the captured groups.
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How to insert a newline in front of a pattern?
...nt something slightly less awkward you could try using perl -pe with match groups instead of sed:
$ echo foo | perl -pe 's/(.*)/\n$1/'
foo
$1 refers to the first matched group in the regular expression, where groups are in parentheses.
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How to reshape data from long to wide format
... provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide format, timevar = the variable containing the values that will be appended to v.names in wide format, direction = wide, and sep = "_". Clear enough? ...
Linq to Entities join vs groupjoin
...nd a simple answer. Can someone please explain (in simple English) what a GroupJoin is? How is it different from a regular inner Join ? Is it commonly used? Is it only for method syntax? What about query syntax? A c# code example would be nice.
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