大约有 42,000 项符合查询结果（耗时：0.0537秒） [XML]
How do I drop a foreign key constraint only if it exists in sql server?
...
The more simple solution is provided in Eric Isaacs's answer. However, it will find constraints on any table. If you want to target a foreign key constraint on a specific table, use this:
IF EXISTS (SELECT *
FROM sys.foreign_keys
WHERE object_id = O...
Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes
...p:ajax process> <f:ajax execute>
The process attribute is server side and can only affect UIComponents implementing EditableValueHolder (input fields) or ActionSource (command fields). The process attribute tells JSF, using a space-separated list of client IDs, which components exactly must...
How do you install ssh-copy-id on a Mac?
I am having trouble trying to install ssh-copy-id on my Mac. I have tried to follow https://github.com/beautifulcode/ssh-copy-id-for-OSX but every time I run ssh-copy-id it gives me errors. Any ideas on how to get ssh-copy-id to install?
...
Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...he primitive type from the getter. Ex:
private Integer num;
public void setNum(Integer i) {
this.num = i;
}
public int getNum() {
return this.num;
}
But in most cases you will want to return the wrapper class.
So either set your DB column to not allow nulls, or use a wrapper ...
GCM with PHP (Google Cloud Messaging)
...
This code will send a GCM message to multiple registration IDs via PHP CURL.
// Payload data you want to send to Android device(s)
// (it will be accessible via intent extras)
$data = array('message' => 'Hello World!');
// The recipient registration tokens for this notifica...
How to use querySelectorAll only for elements that have a specific attribute set?
...ell me what is this syntax input[value][type="checkbox"]:not([value=""] i didnt see this syntax like this before in javascript
– blackHawk
Aug 18 '16 at 9:10
...
In CSS what is the difference between “.” and “#” when declaring a set of styles?
...yles for an element and what are the semantics that come into play when deciding which one to use?
9 Answers
...
JOIN queries vs multiple queries
...ins, multiple queries is much better... look at the following benchmark I did:
Single query with 5 Joins
query: 8.074508 seconds
result size: 2268000
5 queries in a row
combined query time: 0.00262 seconds
result size: 165 (6 + 50 + 7 + 12 + 90)
.
Note that we get the same results in both ...
How to break a line of chained methods in Python?
...l parenthesis:
subkeyword = (
Session.query(Subkeyword.subkeyword_id, Subkeyword.subkeyword_word)
.filter_by(subkeyword_company_id=self.e_company_id)
.filter_by(subkeyword_word=subkeyword_word)
.filter_by(subkeyword_active=True)
.one()
)
...
Rails 3: Get Random Record
... on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1;
share
|
improve this answer
...