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error: command 'gcc' failed with exit status 1 while installing eventlet
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16 Answers
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How to make a new List in Java
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1008
List myList = new ArrayList();
or with generics (Java 7 or later)
List<MyType> myLis...
Unicode equivalents for \w and \b in Java regular expressions?
...ious other properties, too. It now tracks The Unicode Standard, in both RL1.2 and RL1.2a from UTS#18: Unicode Regular Expressions. This is an exciting and dramatic improvement, and the development team is to be commended for this important effort.
Java’s Regex Unicode Problems
The problem wit...
Does MySQL ignore null values on unique constraints?
...ws multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL
1
This i...
select and update database record with a single queryset
...et object update method:
MyModel.objects.filter(pk=some_value).update(field1='some value')
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Check if my app has a new version on AppStore
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91
Here is a simple code snippet that lets you know if the current version is different
-(BOOL) ne...
Display two files side by side
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167
You can use pr to do this, using the -m flag to merge the files, one per column, and -t to omi...
How do I return multiple values from a function? [closed]
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14 Answers
14
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Why is i++ not atomic?
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125
i++ is probably not atomic in Java because atomicity is a special requirement which is not pre...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
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Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
F...