大约有 40,000 项符合查询结果（耗时：0.0213秒） [XML]
Difference between two dates in MySQL
...
SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01');
-- result: 22:00:59, the difference in HH:MM:SS format
SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00');
-- result: 79259 the differenc...
What is the dual table in Oracle?
...
It's a sort of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
...
MySQL: How to copy rows, but change a few fields?
...able
( Event_ID
, col2
...
)
SELECT "155"
, col2
...
FROM Table WHERE Event_ID = "120"
Here, the col2, ... represent the remaining columns (the ones other than Event_ID) in your table.
...
Ordering by specific field value first
...QL FIELD function.
If you want complete sorting for all possible values:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")
If you only care that "core" is first and the other values don't matter:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "co...
Convert INT to VARCHAR SQL
I am using Sybase and I am doing a select which returns me a column called "iftype", but its type is int and I need to convert into varchar. When I try to do the select without the convert function I get this error:
...
ORDER BY the IN value list
... (introduced in PostgreSQL 8.2) VALUES (), ().
Syntax will be like this:
select c.*
from comments c
join (
values
(1,1),
(3,2),
(2,3),
(4,4)
) as x (id, ordering) on c.id = x.id
order by x.ordering
share...
MySQL Orderby a number, Nulls last
...Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://t...
MySQL offset infinite rows
...er. This statement
retrieves all rows from the 96th row
to the last:
SELECT * FROM tbl LIMIT 95, 18446744073709551615;
share
|
improve this answer
|
follow
...
Get names of all files from a folder with Ruby
...ng subdirectories and ".", ".." dotted folders:
Dir.entries("your/folder").select { |f| File.file? File.join("your/folder", f) }
share
|
improve this answer
|
follow
...
IIS7 Permissions Overview - ApplicationPoolIdentity
...eplace this text below if it is named differently)
Open Windows Explorer
Select a file or directory.
Right click the file and select "Properties"
Select the "Security" tab
Click the "Edit" and then "Add" button
Click the "Locations" button and make sure you select the local machine. (Not the Windo...