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How to drop a table if it exists?
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Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent table you can use
I...
What is a NullReferenceException, and how do I fix it?
... to find out where the reference is or isn't set, right-click its name and select "Find All References". You can then place a breakpoint at every found location and run your program with the debugger attached. Every time the debugger breaks on such a breakpoint, you need to determine whether you exp...
Django filter queryset __in for *every* item in list
...query:
In [17]: print Photo.objects.filter(tags=t1).filter(tags=t2).query
SELECT "test_photo"."id"
FROM "test_photo"
INNER JOIN "test_photo_tags" ON ("test_photo"."id" = "test_photo_tags"."photo_id")
INNER JOIN "test_photo_tags" T4 ON ("test_photo"."id" = T4."photo_id")
WHERE ("test_photo_tags"."ta...
How to support UTF-8 encoding in Eclipse
...click Workspace, text file encoding (near bottom) has an encoding chooser.
Select "Other" radio button -> Select UTF-8 from the drop down
Click Apply and OK button OR click simply OK button
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Commit only part of a file in Git
... the file
d do not stage this hunk or any of the later hunks in the file
g select a hunk to go to
/ search for a hunk matching the given regex
j leave this hunk undecided, see next undecided hunk
J leave this hunk undecided, see next hunk
k leave this hunk undecided, see previous undecided hunk
K le...
How to remove a Gitlab project?
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Go to the project page
Select "Settings"
Select the "General" section (you must be in the repository you want to delete to delete it)
If you have enough rights, then at the bottom of the page will be a button for "Advanced settings" (i.e. project s...
Using Tint color on UIImageView
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You can select image in assets and select in right panel default rendering mode
– Nikolay Shubenkov
Oct 22 '15 at 13:48
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Perform commands over ssh with Python
...ease share your knowledge
#!/usr/bin/python
import os
import sys
import select
import paramiko
import time
class Commands:
def __init__(self, retry_time=0):
self.retry_time = retry_time
pass
def run_cmd(self, host_ip, cmd_list):
i = 0
while True:
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Spring Data: “delete by” is supported?
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When you go with query by method (2nd way) it will first do a get call
select * from user where last_name = :firstName
Then it will load it in a List
Then it will call delete id one by one
delete from user where id = 18
delete from user where id = 19
First fetch list of object, then for loo...
Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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