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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?
...use a query like this: "start transaction; create temporary table temporary_table as select * from test where false; copy temporary_table from 'data_file.csv'; lock table test; update test set data=temporary_table.data from temporary_table where test.id=temporary_table.id; insert into test select * ...
Can lambda functions be templated?
...ren't ready to tackle this sort of thing; it'd require more stuff like late_check (where the concept wasn't checked until invoked) and stuff. Simpler was just to drop it all and stick to monomorphic lambdas.
However, with the removal of concepts from C++0x, polymorphic lambdas become a simple propo...
Mocking python function based on input arguments
...
If side_effect is a function then whatever that function returns is
what calls to the mock return. The side_effect function is called with
the same arguments as the mock. This allows you to vary the return
value of the call dy...
Counting the occurrences / frequency of array elements
...be faster than creating an associative array.
– quant_dev
Sep 29 '17 at 20:24
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show 1 more comment
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Removing colors from output
...all conceivable ANSI escape sequences:
./somescript | sed 's/\x1B[@A-Z\\\]^_]\|\x1B\[[0-9:;<=>?]*[-!"#$%&'"'"'()*+,.\/]*[][\\@A-Z^_`a-z{|}~]//g'
(and if you have @edi9999's SI problem, add | sed "s/\x0f//g" to the end; this works for any control char by replacing 0f with the hex of the u...
How would one write object-oriented code in C? [closed]
...
int (*close)(void *self);
int (*read)(void *self, void *buff, size_t max_sz, size_t *p_act_sz);
int (*write)(void *self, void *buff, size_t max_sz, size_t *p_act_sz);
// And data goes here.
} tCommClass;
tCommClass commRs232;
commRs232.open = &rs232Open;
: :
commRs232.write = &...
Drop all tables whose names begin with a certain string
...RE @cmd varchar(4000)
DECLARE cmds CURSOR FOR
SELECT 'drop table [' + Table_Name + ']'
FROM INFORMATION_SCHEMA.TABLES
WHERE Table_Name LIKE 'prefix%'
OPEN cmds
WHILE 1 = 1
BEGIN
FETCH cmds INTO @cmd
IF @@fetch_status != 0 BREAK
EXEC(@cmd)
END
CLOSE cmds;
DEALLOCATE cmds
This is cleane...
Python nonlocal statement
...so that it looks more like the idioms of languages with closures.
def make_counter():
count = 0
def counter():
nonlocal count
count += 1
return count
return counter
Obviously, you could write this as a generator, like:
def counter_generator():
count = 0
...
What is the printf format specifier for bool?
Since ANSI C99 there is _Bool or bool via stdbool.h . But is there also a printf format specifier for bool?
8 Answer...
How do I set bold and italic on UILabel of iPhone/iPad?
...t {
return with([.traitBold, .traitItalic])
}
func with(_ traits: UIFontDescriptor.SymbolicTraits...) -> UIFont {
guard let descriptor = self.fontDescriptor.withSymbolicTraits(UIFontDescriptor.SymbolicTraits(traits).union(self.fontDescriptor.symbolicTraits)) else {
...