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ALTER TABLE to add a composite primary key
...t it after you recreate the primary key.
Also, when using composite keys, order is important.
These
1) ALTER TABLE provider ADD PRIMARY KEY(person,place,thing);
and
2) ALTER TABLE provider ADD PRIMARY KEY(person,thing,place);
are not the the same thing.
They both enforce uniqueness on that set ...
Append a dictionary to a dictionary [duplicate]
...itional copy merging both, you create a lookup chain that searches both in order. Because it doesn't duplicate the mappings it wraps ChainMap uses very little memory, and sees later modifications to any sub-mapping. Because order matters you can also use the chain to layer defaults (i.e. user prefs ...
How to add 'ON DELETE CASCADE' in ALTER TABLE statement
... where constraint_name = theCons and owner = theOwner
order by position;
firstCol BOOLEAN := TRUE;
begin
-- For each constraint
FOR cons IN (select * from user_constraints
where delete_rule = 'NO ACTION'
and constraint_name not l...
Seedable JavaScript random number generator
...a random generator function. SeedRandom can be called with no arguments in order to seed the returned random function with the current time, or it can be called with either 1 or 2 non-negative inters as arguments in order to seed it with those integers. Due to float point accuracy seeding with only ...
The request was aborted: Could not create SSL/TLS secure channel
...
I can't believe something as silly as initialization order solved this problem for me. SMH. Thanks @horgath45!!
– Steve H.
May 2 at 1:51
...
unable to print object ('po') in xcode6 beta 6 osx swift project: (Error in auto-import: failed to g
...has a VERY easy workaround.
So, this is just me posting the fix here, in order to maximize the probability that someone else does a search for this confusing error message, and finds this answer.
So, here it is. In our case, we had an Objective-C project using a mix of Swift and Objective-C frame...
Android: How to handle right to left swipe gestures
...e scroll view get disabled and therefore scroll action does not happen. In order to fix this you need to override the dispatchTouchEvent method of the Activity and return the inherited version of this method after you're done with your own listener.
In order to do a few modifications to Mirek's cod...
Type-juggling and (strict) greater/lesser-than comparisons in PHP
...tors deviate from the computer-scientific definitions in several ways:
In order to constitute an equivalence relation == has to be reflexive, symmetric and transitive:
PHP's == operator is not reflexive, i.e. $a == $a is not always true:
var_dump(NAN == NAN); // bool(false)
Note: The fact that...
How do I add indices to MySQL tables?
...DEX `index_name` (`col1`,`col2`)
Additionally the index should match the order of the query fields. In my extended example the index should be (ProductID,Category) not the other way around.
share
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Is it possible to write to the console in colour in .NET?
...not be garbled. See stackoverflow.com/questions/4812508/…. It's just the order of the write-calls which is not "safe".
– BatteryBackupUnit
Oct 17 '17 at 9:29
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