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psycopg2: insert multiple rows with one query
...("(%s,%s,%s,%s,%s,%s,%s,%s,%s)", x) for x in tup)
cur.execute("INSERT INTO table VALUES " + args_str)
and 2 minutes when using this method:
cur.executemany("INSERT INTO table VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s)", tup)
sh...
For loop example in MySQL
...
drop table if exists foo;
create table foo
(
id int unsigned not null auto_increment primary key,
val smallint unsigned not null default 0
)
engine=innodb;
drop procedure if exists load_foo_test_data;
delimiter #
create procedur...
What is the difference between vmalloc and kmalloc?
...ral virtual-to-physical address mappings will have to be added to the page table. And in the worst case, there will be (size of buffer/page size) number of mappings added to the page table.
This also adds pressure on TLB (the cache entries storing recent virtual to physical address mappings) when a...
✔ Checkmark selected row in UITableViewCell
I am an iOS development newbie. I want to add a checkmark to my UITableViewCell when it is selected. The checkmark should be removed when another row is selected. How would I do this?
...
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...
Postgres manually alter sequence
... ALTER SEQUENCE [sequence] RESTART WITH (SELECT MAX(col) from table); does not work, whereas SELECT setval('sequence', (SELECT (MAX(col) from table), TRUE); does work. I get a syntax error. (Postgres 9.4)
– NuclearPeon
Jul 21 '18 at 1:35
...
Condition within JOIN or WHERE
...in join improve performance for large amount of data with properly indexed tables.
– Shahdat
Oct 6 '16 at 15:13
...
How can I mix LaTeX in with Markdown? [closed]
...eat. I even do some preprocessing on the Markdown so I can do things like tables. But this term I'm teaching a class with a lot of math, and I'd love to be able to put LaTeX formulas with Markdown, something like this:
...
What does “Mass Assignment” mean in Laravel?
...nable by doing this:
protected $guarded = ['*'];
Let's say in your user table you have a field that is user_type and that can have values of user / admin
Obviously, you don't want users to be able to update this value. In theory, if you used the above code, someone could inject into a form a new...
TSQL - How to use GO inside of a BEGIN .. END block?
...t using SET NOEXEC.
IF not whatever
BEGIN
SET NOEXEC ON;
END
ALTER TABLE dbo.EMPLOYEE ADD COLUMN EMP_IS_ADMIN BIT NOT NULL
GO
UPDATE dbo.EMPLOYEE SET EMP_IS_ADMIN = whatever
SET NOEXEC OFF;
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