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MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
...statement insert rows based on explicitly specified values. The INSERT ... SELECT form inserts rows selected from another table or tables.
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SQL query to group by day
...dateadd(DAY,0, datediff(day,0, created)) return '2009-11-02 00:00:00.000'
select sum(amount) as total, dateadd(DAY,0, datediff(day,0, created)) as created
from sales
group by dateadd(DAY,0, datediff(day,0, created))
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PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...and sequences too. Here's what I did:
Tables:
for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do psql -c "alter table \"$tbl\" owner to NEW_OWNER" YOUR_DB ; done
Sequences:
for tbl in `psql -qAt -c "select sequence_name from information_schem...
ReactJS Two components communicating
...te is also increasing in complexity, as we need to
manage active routes, selected tabs, spinners, pagination controls,
and so on.
Managing this ever-changing state is hard. If a model can update
another model, then a view can update a model, which updates another
model, and this, in tur...
In Angular, I need to search objects in an array
...ById')($scope.fish, fish_id);
console.log(found);
$scope.selected = JSON.stringify(found);
}
}]);
If there are any questions just let me know.
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Explicit vs implicit SQL joins
...e joined and how they are joined. Try compare larger SQL queries where you selecting from 8 different tables and you have lots of filtering in the where. By using join syntax you separate out the parts where the tables are joined, to the part where you are filtering the rows.
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Random record from MongoDB
...llection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
{ $match: { a:...
How to remove all namespaces from XML with C#?
... return new XElement(xmlDocument.Name.LocalName, xmlDocument.Elements().Select(el => RemoveAllNamespaces(el)));
}
It's working 100%, but I have not tested it much so it may not cover some special cases... But it is good base to start.
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Use '=' or LIKE to compare strings in SQL?
...
To see the performance difference, try this:
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name = B.name
SELECT count(*)
FROM master..sysobjects as A
JOIN tempdb..sysobjects as B
on A.name LIKE B.name
Comparing strings with '=' is muc...
Indenting code in Sublime text 2?
...gs": { "single_line": false } } will reindent all document without need to select what you want
– Alexis
Apr 22 '15 at 11:43
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