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Postgresql: Conditionally unique constraint
...le slower, the advantage of the exclude solution is that it is deferrable (and by default defers until the end of the statement). In contrast, the accepted unique index solution cannot be deferred (and is checked after every row change). So a bulk update is often not possible because steps during th...
INSERT statement conflicted with the FOREIGN KEY constraint - SQL Server
...he referenced table.
If you have SQL Server Management Studio, open it up and sp_help 'dbo.Sup_Item_Cat'. See which column that FK is on, and which column of which table it references. You're inserting some bad data.
Let me know if you need anything explained better!
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How do I get a reference to the app delegate in Swift?
...off using the delegate accessible through the sharedApplication singleton. And as far as your second question goes, yes you probably want to use a constant. Even though, you may be changing the AppDelegate's properties, you probably won't be reassigning the pointer to anything else, in which case, t...
How to set layout_gravity programmatically?
...apply {
weight = 1.0f
gravity = Gravity.TOP
}
For gravity values and how to set gravity check Gravity.
Basically, you should choose the LayoutParams depending on the parent. It can be RelativeLayout, LinearLayout etc...
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How to convert an image to base64 encoding?
...encode($imagedata);
bear in mind that this will enlarge the data by 33%, and you'll have problems with files whose size exceed your memory_limit.
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Import pandas dataframe column as string not int
I would like to import the following csv as strings not as int64. Pandas read_csv automatically converts it to int64, but I need this column as string.
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Where to find extensions installed folder for Google Chrome on Mac?
...t help, you can always do a custom search.
Go to chrome://extensions/, and find out the ID of an extension (32 lowercase letters) (if not done already, activate "Developer mode" first).
Open the terminal, cd to the directory which is most likely a parent of your Chrome profile (if unsure, try ...
CMake使用教程 - C/C++ - 清泛网 - 专注C/C++及内核技术
...置中使用CheckFunctionExists.cmake
# does this system provide the log and exp functions?
include (CheckFunctionExists.cmake)
check_function_exists (log HAVE_LOG)
check_function_exists (exp HAVE_EXP)
（2）修改.in文件，定义宏。（修改TutorialConfig.h.in，cmake执行中会把宏...
gcc makefile error: “No rule to make target …”
...ionships. If newer tools like SubCons or CMake are not to taste, gcc -MT and gnu make patterns can solve this. See also.
– Nathan Kidd
Mar 14 '13 at 18:09
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Show compose SMS view in Android
I want to send a sms with Android.
14 Answers
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