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PostgreSQL: Is it better to use multiple databases with one schema each, or one database with multip
...context I recommend to use one db with multiple schemas, as you can (e.g.) UNION ALL across schemas, but not across databases. For that reason, a database is really completely insulated from another database while schemas are not insulated from other schemas within the same database.
If you -for so...
What is the PostgreSQL equivalent for ISNULL()
... Coalesce() also handles type promotion properly (exactly like UNION SELECT does), while IsNull() does not.
– ErikE
Feb 7 '10 at 0:03
2
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conditional unique constraint
... records to a table that lacks the constraint, and perhaps use a view with UNION of the two tables to preserve the appearance of a single table.
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Under what circumstances are linked lists useful?
...s contained within the object that's a list element - whether as part of a union (in C terms) or not. Point 3 only applies in languages that let you do it - C, C++, assembler good. Java bad.
– Steve Jessop
Mar 12 '10 at 1:01
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A fast method to round a double to a 32-bit int explained
... but will keep and propagate the sign to the entire 64-bit signed integer. union { double d; int64_t l; } magic; magic.d = input + 6755399441055744.0; magic.l <<= 13; magic.l >>= 13;
– Wojciech Migda
May 13 '16 at...
How do I iterate over an NSArray?
...efault will change to GNU99, which (among other things) supports anonymous unions and structs. That should be nice...
– Quinn Taylor
Jun 15 '09 at 4:13
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What happens to a declared, uninitialized variable in C? Does it have a value?
... is initialized
(recursively) according to these
rules; — if it is a union, the first
named member is initialized
(recursively) according to these
rules.
As to what exactly indeterminate means, I'm not sure for C89, C99 says:
3.17.2 indeterminate valueeither an unspecified value or...
PHP: Move associative array element to beginning of array
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You can use the array union operator (+) to join the original array to a new associative array using the known key (one).
$myArray = array('one' => $myArray['one']) + $myArray;
// or ['one' => $myArray['one']] + $myArray;
Array keys ar...
No == operator found while comparing structs in C++
...d be compared (is there a size somewhere or a sentinel?)
which member of a union to compare
normalisation: for example, date types may allow out-of-range day-of-month or month-of-year, or a rational/fraction object may have 6/8ths while another has 3/4ers, which for performance reasons they correct ...
Chaining multiple filter() in Django, is this a bug?
...ng like this: 'SELECT blog JOIN entry WHERE entry.head_list LIKE "Lennon" UNION SELECT blog JOIN entry WHERE entry.head_list LIKE "Lennon"'
– Johnny Tsang
Jan 27 '14 at 1:57
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