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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
... Not sure why this is the accepted answer... OP is using multi-table inheritance. This answer is only valid for abstract base classes.
– MrName
Mar 12 '18 at 21:39
1
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How do SO_REUSEADDR and SO_REUSEPORT differ?
...dress. Depending on the destination address and the content of the routing table, the system will pick an appropriate source address and replace the "any" binding with a binding to the chosen source IP address.
By default, no two sockets can be bound to the same combination of source address and so...
Infinite Recursion with Jackson JSON and Hibernate JPA issue
...r code like this (I skip the useless parts):
Business Object 1:
@Entity
@Table(name = "ta_trainee", uniqueConstraints = {@UniqueConstraint(columnNames = {"id"})})
public class Trainee extends BusinessObject {
@OneToMany(mappedBy = "trainee", fetch = FetchType.EAGER, cascade = CascadeType.ALL)...
How to get distinct values for non-key column fields in Laravel?
...should use groupby. In Query Builder you can do it this way:
$users = DB::table('users')
->select('id','name', 'email')
->groupBy('name')
->get();
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What's the false operator in C# good for?
...er that nullity could be checked explicitly.
Comparing to SQL, imagine a table Table with 3 rows with value Foo set to true, 3 rows with value Foo set to false and 3 rows with value Foo set to null.
SELECT COUNT(*) FROM Table WHERE Foo = TRUE OR Foo = FALSE
6
In order to count all rows you'd ha...
differentiate null=True, blank=True in django
...e)
The database fields created for PostgreSQL 9.4 are :
CREATE TABLE Test (
id serial NOT NULL,
"charNull" character varying(10),
"charBlank" character varying(10) NOT NULL,
"charNullBlank" character varying(10),
"intNull" in...
selecting unique values from a column
I have a MySQL table which contains the following type of information:
9 Answers
9
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Compile time string hashing
... GCC and not MSVC nor Intel compiler.
Here is the code snippet:
// CRC32 Table (zlib polynomial)
static constexpr uint32_t crc_table[256] = {
0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
0xe0d5e91eL, 0...
brew install mysql on macOS
... like there is something wrong with the set up instructions or the initial tables that are being created. This is how I got mysqld running on my machine.
If the mysqld server is already running on your Mac, stop it first with:
launchctl unload -w ~/Library/LaunchAgents/com.mysql.mysqld.plist
Star...
MySQL's now() +1 day
...and `date`. AFAIR these may be reserved words
my version is:
INSERT INTO `table` ( `data` , `date` ) VALUES('".$date."',NOW()+INTERVAL 1 DAY);
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