大约有 47,000 项符合查询结果（耗时：0.0383秒） [XML]
problem with and :after with CSS in WebKit
I would like to add some style on a select box with the pseudo :after (to style my select box with 2 parts and without images). Here's the HTML:
...
How to make the first option of selected with jQuery
How do I make the first option of selected with jQuery?
27 Answers
27
...
Can you have if-then-else logic in SQL? [duplicate]
I need to do select data from a table based on some kind of priority like so:
7 Answers
...
Fastest way to determine if record exists
...
SELECT TOP 1 products.id FROM products WHERE products.id = ?; will outperform all of your suggestions as it will terminate execution after it finds the first record.
...
Simple way to calculate median with MySQL
...
In MariaDB / MySQL:
SELECT AVG(dd.val) as median_val
FROM (
SELECT d.val, @rownum:=@rownum+1 as `row_number`, @total_rows:=@rownum
FROM data d, (SELECT @rownum:=0) r
WHERE d.val is NOT NULL
-- put some where clause here
ORDER BY d.val
) ...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...for all your queries that need to count everything, even for joins, use *
SELECT boss.boss_id, COUNT(subordinate.*)
FROM boss
LEFT JOIN subordinate on subordinate.boss_id = boss.boss_id
GROUP BY boss.id
But don't use COUNT(*) for LEFT joins, as that will return 1 even if the subordinate table doe...
Simplest way to do a recursive self-join?
...
WITH q AS
(
SELECT *
FROM mytable
WHERE ParentID IS NULL -- this condition defines the ultimate ancestors in your chain, change it as appropriate
UNION ALL
SELECT m.*
FROM mytable m
...
How to select an option from drop down using Selenium WebDriver C#?
I was trying for my web test selecting an option. An example can be found here: http://www.tizag.com/phpT/examples/formex.php
...
How do I limit the number of rows returned by an Oracle query after ordering?
...Oracle in this answer).
To answer the original question, here's the query:
SELECT *
FROM sometable
ORDER BY name
OFFSET 20 ROWS FETCH NEXT 10 ROWS ONLY;
(For earlier Oracle versions, please refer to other answers in this question)
Examples:
Following examples were quoted from linked page, in th...
How to drop all tables in a SQL Server database?
...VARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS t...