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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...
What is the dual table in Oracle?
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It's a sort of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
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How to get the first and last date of the current year?
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SELECT
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()), 0) AS StartOfYear,
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()) + 1, -1) AS EndOfYear
The above query gives a datetime value for midnight at the beginning of December 31. This ...
ORDER BY the IN value list
... (introduced in PostgreSQL 8.2) VALUES (), ().
Syntax will be like this:
select c.*
from comments c
join (
values
(1,1),
(3,2),
(2,3),
(4,4)
) as x (id, ordering) on c.id = x.id
order by x.ordering
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How to use a class from one C# project with another C# project
...Explorer' tree, expand the P2 project and then right-click the project and select 'Add Reference' from the menu.
On the 'Add Reference' dialog, select the 'Projects' tab and select your P1 project.
If you are using namespaces then you will need to import the namespaces for your P1 types by adding ...
How do I compare two files using Eclipse? Is there any option provided by Eclipse?
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To compare two files in Eclipse, first select them in the Project Explorer / Package Explorer / Navigator with control-click. Now right-click on one of the files, and the following context menu will appear. Select Compare With / Each Other.
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How to insert a line break in a SQL Server VARCHAR/NVARCHAR string
...NVARCHAR(100)
SET @text = 'This is line 1.' + CHAR(13) + 'This is line 2.'
SELECT @text
This prints out the following:
This is line 1.
This is line 2.
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PHP PDO returning single row
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$dbh = new PDO(" --- connection string --- ");
$stmt = $dbh->prepare("SELECT name FROM mytable WHERE id=4 LIMIT 1");
$stmt->execute();
$row = $stmt->fetch();
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How can I find which tables reference a given table in Oracle SQL Developer?
... has such option). The following SQL is that one used by PLSQL Developer:
select table_name, constraint_name, status, owner
from all_constraints
where r_owner = :r_owner
and constraint_type = 'R'
and r_constraint_name in
(
select constraint_name from all_constraints
where constraint_type in ...
Find the number of columns in a table
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SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_catalog = 'database_name' -- the database
AND table_name = 'table_name'
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