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Correct use of Multimapping in Dapper
...rId.
There is a big caveat here, if the column ordering in the underlying table is flipped for some reason:
ProductID | ProductName | AccountOpened | CustomerName | CustomerId
--------------------------------------- -------------------------
splitOn: CustomerId will result in a null custo...
What is an ORM, how does it work, and how should I use one? [closed]
...(book);
}
With an ORM library, it would look like this:
book_list = BookTable.query(author="Linus");
The mechanical part is taken care of automatically via the ORM library.
Pros and Cons
Using ORM saves a lot of time because:
DRY: You write your data model in only one place, and it's easier...
Which MySQL datatype to use for an IP address? [duplicate]
... INT UNSIGNED
And INET_ATON and INET_NTOA to convert them:
INSERT INTO `table` (`ipv4`) VALUES (INET_ATON("127.0.0.1"));
SELECT INET_NTOA(`ipv4`) FROM `table`;
For IPv6 addresses you could use a BINARY instead:
`ipv6` BINARY(16)
And use PHP’s inet_pton and inet_ntop for conversion:
'INSER...
How do I set the time zone of MySQL?
...ed timezones like 'Europe/Helsinki' means that you have to have a timezone table properly populated.)
Keep in mind that +02:00 is an offset. Europe/Berlin is a timezone (that has two offsets) and CEST is a clock time that corresponds to a specific offset.
@@session.time_zone variable
SELECT @@ses...
How to use NULL or empty string in SQL
...
Select *
From Table
Where (col is null or col = '')
Or
Select *
From Table
Where IsNull(col, '') = ''
share
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improve this answer
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SQLite - UPSERT *not* INSERT or REPLACE
...
Assuming three columns in the table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will insert or replace 2 of the...
AWS MySQL RDS vs AWS DynamoDB [closed]
I've been using MySQL for a fair while now and I'm comfortable with its structure & SQL Queries etc.
4 Answers
...
SQL Server: Difference between PARTITION BY and GROUP BY
...
We can take a simple example.
Consider a table named TableA with the following values:
id firstname lastname Mark
-------------------------------------------------------------------
1 arun prasanth ...
How does MySQL process ORDER BY and LIMIT in a query?
...row.
select t.article
from
(select article, publish_date
from table1
order by publish_date desc limit 10) t
order by t.publish_date asc;
If you need all columns, it is done this way:
select t.*
from
(select *
from table1
order by publish_date desc limit 10) ...
CSS to make HTML page footer stay at bottom of the page with a minimum height, but not overlap the p
...w are 4 different methods of mine:
In each example the texts are freely-editable to illustrate how the content would render in different scenarios.
1) Flexbox
body{ height:100vh; margin:0; }
header{ min-height:50px; background:lightcyan; }
footer{ min-height:50px; background:PapayaWhip; }
/* ...