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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
...
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...
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
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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.
...
How to change the blue highlight color of a UITableViewCell?
I'm wondering how to change the blue highlight/selection color of a UITableViewCell , any ideas?
11 Answers
...
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 ...
How to declare variable and use it in the same Oracle SQL script?
...or
DEFINE stupidvar = 'stupidvarcontent';
SELECT stupiddata
FROM stupidtable
WHERE stupidcolumn = '&stupidvar'
upd:
SQL*Plus: Release 10.2.0.1.0 - Production on Wed Aug 25 17:13:26 2010
Copyright (c) 1982, 2005, Oracle. All rights reserved.
SQL> conn od/od@etalon
Connected.
SQL>...
How to iterate over array of objects in Handlebars?
...t;script id="small-template" type="text/x-handlebars-template">
<table>
<thead>
<th>Username</th>
<th>email</th>
</thead>
<tbody>
{{#data}}
<tr>
...
How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
...ting to object
Converting to resource
Converting to NULL
Type comparison table
As reference and example you can see the comparison table in the manual:
Loose comparisons with ==
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