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SQL - HAVING vs. WHERE
...ows; HAVING clause introduces a condition on aggregations, i.e. results of selection where a single result, such as count, average, min, max, or sum, has been produced from multiple rows. Your query calls for a second kind of condition (i.e. a condition on an aggregation) hence HAVING works correctl...
How to change an Eclipse default project into a Java project
.... Taking a backup is very recommended!
How to do it just using Eclipse?
Select project.
Open the project properties through Project -> Properties.
Go to "Targetted Runtimes" and add the proper runtime. Click APPLY.
Go to "Project Facets" and select the JAVA facet which has appeared due to step...
Unbound classpath container in Eclipse
... or 4. goto Properties -> Java Build Path -> Libraries Tab -> Select the erroneous system library -> Edit (On the right) -> Select alternate JRE -> Finish.
– Rajkiran
Jun 26 '14 at 12:11
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Multiple line code example in Javadoc comment
...se of Eclipse, this is because of (bugged?) javadoc utility. If you have @ character in the multiline code inside {@code ...multiline...} then javadoc fails to parse it correctly:( At least this is what I see with Oracle JDK1.7.0_45 javadoc implementation.
– Male
...
How to select date without time in SQL
When I select date in SQL it is returned as 2011-02-25 21:17:33.933 . But I need only the Date part, that is 2011-02-25 . How can I do this?
...
How do you beta test an iphone app?
...file
Start the Mac OS utility program Keychain Access.
In its main menu, select Keychain Access / Certificate Assistant / Request a Certificate From a Certificate Authority...
The dialog that pops up should aready have your email and name it it.
Select the radio button Saved to disk and Continue....
How to get the connection String from a database
... Visual Studio go to Tools -> Connect to Database.
2] Under Server Name Select your Database Server Name (Let the list Populate if its taking time).
3] Under Connect to a Database, Select Select or enter a database name.
4] Select your Database from Dropdown.
5] After selecting Database try Test ...
How to make a query with group_concat in sql server [duplicate]
...
Query:
SELECT
m.maskid
, m.maskname
, m.schoolid
, s.schoolname
, maskdetail = STUFF((
SELECT ',' + md.maskdetail
FROM dbo.maskdetails md
WHERE m.maskid = md.maskid
FOR X...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...k around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's outpu...
Retrieve the maximum length of a VARCHAR column in SQL Server
...
Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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