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How do I add a foreign key to an existing SQLite table?
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SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as follows:
CREATE TABLE child (
id INTEGER PRIMARY KEY,
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Setting up FTP on Amazon Cloud Server [closed]
... to set up FTP on Amazon Cloud Server, but without luck.
I search over net and there is no concrete steps how to do it.
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html (+css): denoting a preferred place for a line break
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By using
span.avoidwrap { display:inline-block; }
and wrapping the text I want to be kept together in
<span class="avoidwrap"> Text </span>
it will wrap first in preferred blocks and then in smaller fragments as needed.
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Regex to check whether a string contains only numbers [duplicate]
I get false on both "123" and "123f" . I would like to check if the hash only contains numbers. Did I miss something?
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When should std::move be used on a function return value? [duplicate]
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met save for the fact that the source object is a function parameter,
and the object to be copied is designated by an lvalue, overload
resolution to select the constructor for the copy is first performed as
if the object were designated by an rvalue.
return foo; is a case of NRVO, so cop...
Traits vs. interfaces
I've been trying to study up on PHP lately, and I find myself getting hung up on traits. I understand the concept of horizontal code reuse and not wanting to necessarily inherit from an abstract class. What I don't understand is: What is the crucial difference between using traits versus interfaces?...
How to turn on/off ReactJS 'development mode'?
...he other answer assumes you are using external pre-built files from react, and while correct that is not how most folks are going to or should consume React as a package. Moreover, at this point most every React library and package also relies on the same convention to toggle dev time helpers off du...
What does the “__block” keyword mean?
...eated in a special way when it is used inside a block. Normally, variables and their contents that are also used in blocks are copied, thus any modification done to these variables don't show outside the block. When they are marked with __block, the modifications done inside the block are also visib...
Live-stream video from one android phone to another over WiFi
...nternet for days now on how to implement a video streaming feature from an android phone to another android phone over a WiFi connection but I can't seem to find anything useful. I looked on android developers for sample code, stackoverflow, google, android blogs but nothing. All I can find are some...
Setting default values for columns in JPA
Is it possible to set a default value for columns in JPA, and if, how is it done using annotations?
18 Answers
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