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How to remove all MySQL tables from the command-line without DROP database permissions? [duplicate]
...ts to execute it:
SET FOREIGN_KEY_CHECKS = 0;
SET @tables = NULL;
SELECT GROUP_CONCAT('`', table_schema, '`.`', table_name, '`') INTO @tables
FROM information_schema.tables
WHERE table_schema = 'database_name'; -- specify DB name here.
SET @tables = CONCAT('DROP TABLE ', @tables);
PREPARE st...
SQL query for finding records where count > 1
...
Use the HAVING clause and GROUP By the fields that make the row unique
The below will find
all users that have more than one payment per day with the same account number
SELECT
user_id ,
COUNT(*) count
FROM
PAYMENT
GROUP BY
account,
use...
Showing the same file in both columns of a Sublime Text window
...indowCommand):
def run(self):
w = self.window
if w.num_groups() == 1:
w.run_command('set_layout', {
'cols': [0.0, 1.0],
'rows': [0.0, 0.33, 1.0],
'cells': [[0, 0, 1, 1], [0, 1, 1, 2]]
})
w.focus_g...
Testing modules in rspec
...llo.should == "hallo" }
end
It might seem wrong to hijack nested example groups, but I like the terseness. Any thoughts?
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Count the occurrences of DISTINCT values
...
SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
... far the least performant for the provided example. Furthermore, while the groupby method is only slightly less performant, I find the duplicated method to be more readable.
Using the sample data provided:
>>> %timeit df3.reset_index().drop_duplicates(subset='index', keep='first').set_index...
How do I trim whitespace?
...e('\\s*(.*\\S)?\\s*')
>>> m=p.match(' \t blah ')
>>> m.group(1)
'blah'
>>> m=p.match(' \tbl ah \t ')
>>> m.group(1)
'bl ah'
>>> m=p.match(' \t ')
>>> print m.group(1)
None
Searching (you have to handle the "only spaces" input case diffe...
best way to add license section to iOS settings bundle
...to solve all the problems I was running into.
It seems to be best to use group element titles to hold the licenses (this is what Apple do in the iWork apps). There is however a limit on the length of these (and I've not yet discovered exactly what the limit is), so you need to break each license f...
Linq to Objects: does GroupBy preserve order of elements?
Does Enumerable.GroupBy from LINQ to Objects preserve order of elements in the groups?
1 Answer
...
How to include “zero” / “0” results in COUNT aggregate?
...erson
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is working, is that the outer (left) join will return NULL for those persons that do not have an appointment. The aggregate function count() will not count NULL values and thus...