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PostgreSQL: How to pass parameters from command line?
...3="'2010-11-12'"
and then refer to the variables in sql as :v1, :v2 etc
select * from table_1 where id = :v1;
Please pay attention on how we pass string/date value using two quotes " '...' "
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Insert new column into table in sqlite?
... populate it with the old data:
INSERT INTO {tableName} (name, qty, rate) SELECT name, qty, rate FROM TempOldTable;
Then delete the old table:
DROP TABLE TempOldTable;
I'd much prefer the second option, as it will allow you to completely rename everything if need be.
...
What is the difference between UNION and UNION ALL?
...want the duplicates (especially when developing reports).
UNION Example:
SELECT 'foo' AS bar UNION SELECT 'foo' AS bar
Result:
+-----+
| bar |
+-----+
| foo |
+-----+
1 row in set (0.00 sec)
UNION ALL example:
SELECT 'foo' AS bar UNION ALL SELECT 'foo' AS bar
Result:
+-----+
| bar |
+---...
How to get size of mysql database?
...
Run this query and you'll probably get what you're looking for:
SELECT table_schema "DB Name",
ROUND(SUM(data_length + index_length) / 1024 / 1024, 1) "DB Size in MB"
FROM information_schema.tables
GROUP BY table_schema;
This query comes from the mysql forums, where there are...
phpunit mock method multiple calls with different arguments
... ->with($this->logicalOr(
$this->equalTo('select * from roles'),
$this->equalTo('select * from users')
))
->will($this->returnCallback(array($this, 'myCallback')));
var_dump($mock->Query("select * from us...
SQL Server: Filter output of sp_who2
... SPID_1 INT,
REQUESTID INT
)
INSERT INTO @Table EXEC sp_who2
SELECT *
FROM @Table
WHERE ....
And filter on what you require.
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Get current AUTO_INCREMENT value for any table
...'TableName' ;
You can get exactly this information by using this query:
SELECT `AUTO_INCREMENT`
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'DatabaseName'
AND TABLE_NAME = 'TableName';
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When and why would you seal a class?
... think this post has some good point, the specific case was when trying to cast a non-sealed class to any random interface, compiler doesn't throw error; but when sealed is used the compiler throws error that it can't convert. Sealed class brings additional code access security.
https://www.codeproj...
Difference between SelectedItem, SelectedValue and SelectedValuePath
...
Their names can be a bit confusing :). Here's a summary:
The SelectedItem property returns the entire object that your list is bound to. So say you've bound a list to a collection of Category objects (with each Category object having Name and ID properties). eg. ObservableCollection&l...
LINQ to SQL Left Outer Join
...table), where-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
s...