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What is the purpose of Flask's context stacks?
...alues in a script that should be run from the shell. For example, a "setup_tables.py" script...
from myapp import app, db
# Set up models
db.create_all()
In this case, the Flask-SQLAlchemy extension knows about the app application, but during create_all() it will throw an error complaining about...
How to display the function, procedure, triggers source code in postgresql?
.... Just know the following way, may be it will help you!
step 1 : Get the table oid of the trigger:
skytf=> select tgrelid from pg_trigger where tgname='insert_tbl_tmp_trigger';
tgrelid
---------
26599
(1 row)
step 2: Get the table name of the above oid !
s...
Finding the id of a parent div using Jquery
...
This can be easily done by doing:
$(this).closest('table').attr('id');
You attach this to any object inside a table and it will return you the id of that table.
share
|
imp...
Understanding “randomness”
...et after multiplying two random variables:
BarChart[BinCounts[Table[RandomReal[{0, 1}, 50000] *
RandomReal[{0, 1}, 50000], {50000}], 0.01]]
So, both are “random”, but their distribution is very different.
Another example
While 2 * Random() is un...
Transitions on the CSS display property
...es up space, and is still rendered inline or as a block or block-inline or table or whatever the display element tells it to render as, and takes up space accordingly.
Other elements do not automatically move to occupy that space. The hidden element just doesn’t render its actual pixels to the out...
static const vs #define
... The pro and cons are mixed up, I would be very like to see a comparison table.
– Unknown123
Apr 25 '19 at 3:49
...
Large Object Heap Fragmentation
...is is a very interesting lead, thanks. Completely forgot about the intern table. I know one of our developers is a keen interner so this is definitely something I shall investigate.
– Paul Ruane
Mar 27 '09 at 10:34
...
How to handle click event in Button Column in Datagridview?
... using this exact example for a dgv with two columns. One column that's editable and the 2nd with a remove buttton. I click all over the dgv and the event only fires off when I click on the button.
– Luminous
Aug 22 '14 at 14:04
...
SQL中使用update inner join和delete inner join；Oracle delete join替代...
...> 0
and mw.size > 1;
下面是Oracle的：
Sql代码
DELETE TABLE1 where KHID exists ( select KHID from table2 where FWDWID=8)
Sql代码
DELETE TABLE1 where exists ( select 1 from table2 where and table1.khid=table2.khid and FWDWID=8);
Oracle的delete与join如何使用
...
SQL Server: Examples of PIVOTing String data
...on will work on text as well as numbers. This query will only require the table to be scanned once.
SELECT Action,
MAX( CASE data WHEN 'View' THEN data ELSE '' END ) ViewCol,
MAX( CASE data WHEN 'Edit' THEN data ELSE '' END ) EditCol
FROM t
GROUP BY Action
...