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How to get the last date of a particular month with JodaTime?
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edited Jun 20 at 9:12
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answered Mar 14 '12 at 22:47
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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...
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...
How do I return multiple values from a function? [closed]
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14 Answers
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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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Linux bpftrace学习笔记（持续更新） - 操作系统(内核) - 清泛网移动版 - ...
...BPF性能工具及其可见性bpftrace安装请参考：bpftrace-install。1、查看程序在打开哪些文件： bpftrace -e & 39;tracepoint:syscalls:sys_enter_open { printf("%s %s n
图：BPF性能工具及其可见性
bpftrace安装请参考：bpftrace-install 。
1、查看哪些程...
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...
Measure execution time for a Java method [duplicate]
...em.out.println(stopTime - startTime);
In Java 8 (output format is ISO-8601):
Instant start = Instant.now();
Thread.sleep(63553);
Instant end = Instant.now();
System.out.println(Duration.between(start, end)); // prints PT1M3.553S
Guava Stopwatch:
Stopwatch stopwatch = Stopwatch.createStarted()...