大约有 40,000 项符合查询结果（耗时：0.0389秒） [XML]
How to drop column with constraint?
...ing of constraints script:
DECLARE @sql NVARCHAR(MAX)
WHILE 1=1
BEGIN
SELECT TOP 1 @sql = N'alter table tbloffers drop constraint ['+dc.NAME+N']'
from sys.default_constraints dc
JOIN sys.columns c
ON c.default_object_id = dc.object_id
WHERE
dc.parent_object_id = OBJ...
SQL to determine minimum sequential days of access?
...
The answer is obviously:
SELECT DISTINCT UserId
FROM UserHistory uh1
WHERE (
SELECT COUNT(*)
FROM UserHistory uh2
WHERE uh2.CreationDate
BETWEEN uh1.CreationDate AND DATEADD(d, @days, uh1.CreationDate)
) = @days O...
Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
...
SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
Add disabled attribute to input element using Javascript
...
Working code from my sources:
HTML WORLD
<select name="select_from" disabled>...</select>
JS WORLD
var from = jQuery('select[name=select_from]');
//add disabled
from.attr('disabled', 'disabled');
//remove it
from.removeAttr("disabled");
...
IntelliJ IDEA way of editing multiple lines
...ossibility to edit multiple lines.
Use:
Alt + Shift + Mouse click
for selection. More about this new improvement in IntelliJ blogpost here. Very useful feature.
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Remove all spaces from a string in SQL Server
...
Simply replace it;
SELECT REPLACE(fld_or_variable, ' ', '')
Edit:
Just to clarify; its a global replace, there is no need to trim() or worry about multiple spaces for either char or varchar:
create table #t (
c char(8),
v varchar(8))...
Make Visual Studio understand CamelCase when hitting Ctrl and cursor keys
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Is there an option, to select the whole word, even if CameHumps is on? At the moment I have to press right or left several times to select a word. I hope you get me.
– Ozkan
Oct 7 '16 at 14:01
...
Select TreeView Node on right click before displaying ContextMenu
I would like to select a WPF TreeView Node on right click, right before the ContextMenu displayed.
11 Answers
...
Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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