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What is the dual table in Oracle?
...
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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Change auto increment starting number?
...foobar(moobar) values ("def");
INSERT INTO foobar(moobar) values ("xyz");
select * from foobar;
'10', 'abc'
'11', 'def'
'12', 'xyz'
This auto increments the id column by one starting at 10.
Auto increment in MySQL by 5, starting at 10:
drop table foobar
create table foobar(
id IN...
Are “while(true)” loops so bad? [closed]
...// do something with the line
}
And in C, it's
#include <stdio.h>
char* buffer = NULL;
size_t buffer_size;
size_t size_read;
while( (size_read = getline(&buffer, &buffer_size, stdin)) != -1 ){
// do something with the line
}
free(buffer);
or if you're convinced you know how long...
Inserting multiple rows in a single SQL query? [duplicate]
...much better methods as seen in the other answers.
You can use INSERT with SELECT UNION ALL:
INSERT INTO MyTable (FirstCol, SecondCol)
SELECT 'First' ,1
UNION ALL
SELECT 'Second' ,2
UNION ALL
SELECT 'Third' ,3
...
Only for small datasets though, which should be fine for your 4 rec...
The cast to value type 'Int32' failed because the materialized value is null
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where u.ID == userID
select (int?)ch.Amount).Sum() ?? 0;
This first casts to int? to tell the C# compiler that this expression can indeed return null, even though Sum() returns an int. Then we use the normal ?? operator to handle the null case....
How do I write LINQ's .Skip(1000).Take(100) in pure SQL?
...W_NUMBER function. eg.
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 51 AND 60; --BETWEEN is inclusive
...
Database development mistakes made by application developers [closed]
... the log output from Hibernate and you'll see all the queries begin with:
SELECT DISTINCT ...
This is a bit of a shortcut to ensuring you don't return duplicate rows and thus get duplicate objects. You'll sometimes see people doing this as well. If you see it too much it's a real red flag. Not...
How to execute IN() SQL queries with Spring's JDBCTemplate effectivly?
...ters.addValue("ids", ids);
List<Foo> foo = getJdbcTemplate().query("SELECT * FROM foo WHERE a IN (:ids)",
parameters, getRowMapper());
This only works if getJdbcTemplate() returns an instance of type NamedParameterJdbcTemplate
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C# - Selectively suppress custom Obsolete warnings
... },
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
});
}
});
...
How can I view the shared preferences file using Android Studio?
...in. 4. Start Android Emulator (in my case API 24) 5. Launch stetho-sample (select it from run configuration menu next to green arrow 6. On your PC open latest Chrome browser 7. go by chrome://inspect address 8. chose your emulator in list. 9. In opened window go to Resources tab. 10. Find your share...