大约有 13,000 项符合查询结果（耗时：0.0255秒） [XML]
How to 'insert if not exists' in MySQL?
...
Solution:
INSERT INTO `table` (`value1`, `value2`)
SELECT 'stuff for value1', 'stuff for value2' FROM DUAL
WHERE NOT EXISTS (SELECT * FROM `table`
WHERE `value1`='stuff for value1' AND `value2`='stuff for value2' LIMIT 1)
Explanation:
The innermost query
SELECT *...
In Eclipse, can I have multiple Console views at once, each showing a different Console?
...nsole views.
One of your other buttons near your console tab is "Display Selected Console". When you choose this option you can select from any of your running applications.
Just select the tab, select which application you want it to watch, and repeat for the other tab.
You can then move your ...
html (+css): denoting a preferred place for a line break
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Works great - when it is important, that chars like "-" non break. Example: Perikles <span class="avoidwrap">(um&nbsp;500-429&nbsp;v.Chr.)</span>
– Sarah Trees
May 19 '15 at 17:37
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Retrieve column names from java.sql.ResultSet
... metadata. See ResultSetMetaData
e.g.
ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
ResultSetMetaData rsmd = rs.getMetaData();
String name = rsmd.getColumnName(1);
and you can get the column name from there. If you do
select x as y from table
then rsmd.getColumnLabel() wi...
Condition within JOIN or WHERE
...of filtering criteria more easily maintainable.
For example, instead of:
SELECT *
FROM Customers c
INNER JOIN CustomerAccounts ca
ON ca.CustomerID = c.CustomerID
AND c.State = 'NY'
INNER JOIN Accounts a
ON ca.AccountID = a.AccountID
AND a.Status = 1
Write:
SELECT *
FROM Customer...
How to link a Facebook app with an existing fan page
...roducts").
Change your page name to mach your App name.
Go to your App and select "App Details"
Under "Contact Info" you will find "App Page". There you will be able to create a new page or if all went well, select your page from a list.
I found the info in the little question-mark next to "App pa...
Select element by exact match of its content
All right, I wonder if there is a way to make the :contains() jQuery's selector to select elements with only the string that is typed in
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Converting a Java Keystore into PEM Format
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KeyStore ks = KeyStore.getInstance("jks");
/* Load the key store. */
...
char[] password = ...;
/* Save the private key. */
FileOutputStream kos = new FileOutputStream("tmpkey.der");
Key pvt = ks.getKey("your_alias", password);
kos.write(pvt.getEncoded());
kos.flush();
kos.close();
/* Save the cer...
The import javax.servlet can't be resolved [duplicate]
...ibraries tab
Click Add External JARs...
Browse to find servlet-api.jar and select it.
Click OK to update the build path.
Or, if you copy the JAR into your project:
Right-click the project, click Properties.
Choose Java Build Path.
Click Add JARs...
Find servlet-api.jar in your project and select...
Visual Studio: How to break on handled exceptions?
...the VS2010 environement, by going to "Tools", "Import Export Settings" and select a reset to the C# environment... it contains the Exceptions Submenu item
– BeardinaSuit
Feb 14 '12 at 16:28
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