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MySQL: selecting rows where a column is null
...for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows.
...
How to get current date & time in MySQL?
...ccepted answers, I think this way is also possible:
Create your 'servers' table as following :
CREATE TABLE `servers`
(
id int(11) NOT NULL PRIMARY KEY auto_increment,
server_name varchar(45) NOT NULL,
online_status varchar(45) NOT NULL,
_exchange varchar(45) NOT NULL,
...
Is floating point math broken?
...754 is anything with an error of less than one unit in the last place. The table of reciprocals of Y (1/Y) is known as the quotient selection table (QST) in the slow division, and the size in bits of the quotient selection table is usually the width of the radix, or a number of bits of the quotient ...
How to escape apostrophe (') in MySql?
...y be written as “''”.
(Also, you linked to the MySQL 5.0 version of Table 8.1. Special Character Escape Sequences, and the current version is 5.6 — but the current Table 8.1. Special Character Escape Sequences looks pretty similar.)
I think the Postgres note on the backslash_quote (string)...
SELECT * WHERE NOT EXISTS
...
You didn't join the table in your query.
Your original query will always return nothing unless there are no records at all in eotm_dyn, in which case it will return everything.
Assuming these tables should be joined on employeeID, use the foll...
How to add a footer to a UITableView in Storyboard
...
You can just drag a view to the bottom area of the tableView. You'll see in the hierarchy that it will be a subview of the tableview. You can then drag subviews such as labels and buttons there, adjust the height, etc.
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How can I edit a view using phpMyAdmin 3.2.4?
...
In your database table list it should show View in Type column.
To edit View:
Click on your View in table list
Click on Structure tab
Click on Edit View under Check All
Hope this help
update: in PHPMyAdmin 4.x, it doesn't show View in ...
What is PAGEIOLATCH_SH wait type in SQL Server?
...stem.
In practice, this almost always happens due to large scans over big tables. It almost never happens in queries that use indexes efficiently.
If your query is like this:
Select * from <table> where <col1> = <value> order by <PrimaryKey>
, check that you have a composit...
Versioning SQL Server database
...N to N+1. (These go in your version control system.) A _version_history_ table, something like
create table VersionHistory (
Version int primary key,
UpgradeStart datetime not null,
UpgradeEnd datetime
);
gets a new entry every time an upgrade script runs which corresponds to th...
What does multicore assembly language look like?
.... All that's needed is software support for each thread to set up its own tables and messaging queues. The OS uses those to do the actual multi-threaded scheduling.
As far as the actual assembly is concerned, as Nicholas wrote, there's no difference between the assemblies for a single threaded or...