大约有 5,880 项符合查询结果（耗时：0.0201秒） [XML]
postgresql - sql - count of `true` values
In the above table, if I do :
10 Answers
10
...
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...
Why unsigned integer is not available in PostgreSQL?
...ter solution would be Postgres adding unsigned as a first class type. In a table with 20 million records, with and indexed field like this, you are wasting 40MB of space on unused bits. If you are abusing that across another 20 tables, you're now wasting 800MB of space.
– tpart...
What data type to use for hashed password field and what length?
...cker gains access to your database, they'd have to construct their rainbow table based on that salt. And that's just as much work as simply guessing the password.
– Bill Karwin
Sep 16 '10 at 7:14
...
Difference between JOIN and INNER JOIN
...specify CROSS JOIN.
OR
For an inner join, the syntax is:
SELECT ...
FROM TableA
[INNER] JOIN TableB
(in other words, the "INNER" keyword is optional - results are the same
with or without it)
share
|
...
is of a type that is invalid for use as a key column in an index
...bytes even then so the safest maximum size for your keys would be:
create table [misc_info]
(
[id] INTEGER PRIMARY KEY IDENTITY NOT NULL,
[key] nvarchar(450) UNIQUE NOT NULL,
[value] nvarchar(max) NOT NULL
)
i.e. the key can't be over 450 characters. If you can switch to varchar i...
Ruby on Rails: how do I sort with two columns using ActiveRecord?
...s, you should use the following more robust version: :order => ["DATE(#{table_name}.updated_at)", :price] (Note that :price is a symbol.)
– Jo Liss
Jul 31 '12 at 17:32
...
Saving results with headers in Sql Server Management Studio
...
Try the Export Wizard. In this example I select a whole table, but you can just as easily specify a query:
(you can also specify a query here)
share
|
improve t...
to drawRect or not to drawRect (when should one use drawRect/Core Graphics vs subviews/images and wh
...it would be more complicated.
The general workflow should be to build the tableviews with subviews. Use Instruments to measure the frame rate on the oldest hardware your app will support. If you can't get 60fps, drop down to CoreGraphics. When you've done this for a while, you get a sense for when ...
MySQL SELECT WHERE datetime matches day (and not necessarily time)
I have a table which contains a datetime column. I wish to return all records of a given day regardless of the time. Or in other words, if my table only contained the following 4 records, then only the 2nd and 3rd would be returned if I limit to 2012-12-25.
...