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Django database query: How to get object by id?
...ject, using get() is more straightforward:
obj = Class.objects.get(pk=this_object_id)
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Should all Python classes extend object?
...;>> class Bar(object): pass
...
>>> type(Bar())
<class '__main__.Bar'>
Also the rules for multiple inheritance are different in ways that I won't even try to summarize here. All good documentation that I've seen about MI describes new-style classes.
Finally, old-style classe...
Can PostgreSQL index array columns?
...0}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because we have only 2 records for this test...
SET enable_seqscan TO off;
EXPLAIN ANALYZE
SELECT * FROM "Test" WHERE "Column1" @> ARRAY[2...
Adding a new value to an existing ENUM Type
...he new type.
-- 1. rename the enum type you want to change
alter type some_enum_type rename to _some_enum_type;
-- 2. create new type
create type some_enum_type as enum ('old', 'values', 'and', 'new', 'ones');
-- 3. rename column(s) which uses our enum type
alter table some_table rename column some...
Programmatically retrieve memory usage on iPhone
...icture of usage over-all.
#import <mach/mach.h>
// ...
void report_memory(void) {
struct task_basic_info info;
mach_msg_type_number_t size = TASK_BASIC_INFO_COUNT;
kern_return_t kerr = task_info(mach_task_self(),
TASK_BASIC_INFO,
...
Separation of business logic and data access in django
...ule and each command is represented as a function.
services.py
def activate_user(user_id):
user = User.objects.get(pk=user_id)
# set active flag
user.active = True
user.save()
# mail user
send_mail(...)
# etc etc
Using forms
The other way is to use a Django Form for e...
C# binary literals
...t separators via underscore characters).
An example:
int myValue = 0b0010_0110_0000_0011;
You can also find more information on the Roslyn GitHub page.
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libunwind链接时报错：undefined reference to `_Ux86_64_init_local\' - ...
libunwind链接时报错：undefined reference to `_Ux86_64_init_local'编译安装libunwind后，代码编译链接时报错：undefined reference to `_Ux86_64_init_local& 39;，链接选项加了 -lunwind，仍然报错。原因：编译出来的libunwind拆分成了很多个 编译安装libunwi...
How to print SQL statement in codeigniter model
...
To display the query string:
print_r($this->db->last_query());
To display the query result:
print_r($query);
The Profiler Class will display benchmark results, queries you have run, and $_POST data at the bottom of your pages.
To enable the p...
PHP: Storing 'objects' inside the $_SESSION
I just figured out that I can actually store objects in the $_SESSION and I find it quite cool because when I jump to another page I still have my object. Now before I start using this approach I would like to find out if it is really such a good idea or if there are potential pitfalls involved....