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Equals(=) vs. LIKE
...perations
MAX, MIN, DISTINCT, references to a grouping column, and the
UNION, EXCEPT, and INTERSECT operators refer to character
strings, the specific value selected by these operations from
a set of such equal values is implementation-dependent.
(Emphasis added.)
What does this mean? It ...
How to return result of a SELECT inside a function in PostgreSQL?
...hink you need a RETURN; before that END;, at least I did - but I'm doing a UNION so I'm not sure if that makes it different.
– yekta
Sep 4 '13 at 15:08
...
C char array initialization
...y way at any time in the program, provided they are members of a struct or union.
Example program:
#include <stdio.h>
struct ccont
{
char array[32];
};
struct icont
{
int array[32];
};
int main()
{
int cnt;
char carray[32] = { 'A', 66, 6*11+1 }; // 'A', 'B', 'C', '\0', '\0', ....
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
...
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
...
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
2
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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...