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What is PAGEIOLATCH_SH wait type in SQL Server?
...ppens in queries that use indexes efficiently.
If your query is like this:
Select * from <table> where <col1> = <value> order by <PrimaryKey>
, check that you have a composite index on (col1, col_primary_key).
If you don't have one, then you'll need either a full INDEX SCAN ...
JPQL IN clause: Java-Arrays (or Lists, Sets…)?
... for JPA 1.0 but you can pass a Collection in JPA 2.0:
String qlString = "select item from Item item where item.name IN :names";
Query q = em.createQuery(qlString, Item.class);
List<String> names = Arrays.asList("foo", "bar");
q.setParameter("names", names);
List<Item> actual = q.get...
When to use Preorder, Postorder, and Inorder Binary Search Tree Traversal strategies
... Pre-Order, In-order or Post-Order?
The traversal strategy the programmer selects depends on the specific needs of the algorithm being designed. The goal is speed, so pick the strategy that brings you the nodes you require the fastest.
If you know you need to explore the roots before inspecting ...
How do I change the color of radio buttons?
...self consists of a round shape and a dot at the center (when the button is selected). What I want to change is the color of both. Can this be done using CSS?
...
Should services always return DTOs, or can they also return domain models?
...lection of domain models (with a .ToArray() or ToList(), for instance) you select all columns to populate the realized objects. If you project the DTO in the query instead, EF is smart enought to select only the columns required to populate your DTO, which can be significantly less data to transfer ...
What do Clustered and Non clustered index actually mean?
...CLARE @C1 AS CURSOR,
@X AS INT
SET @C1 = CURSOR FAST_FORWARD
FOR SELECT number
FROM master..spt_values
WHERE type = 'P'
AND number BETWEEN 1 AND 100
ORDER BY CRYPT_GEN_RANDOM(4)
OPEN @C1;
FETCH NEXT FROM @C1 INTO @X;
WHILE @@FETCH_STATUS = 0
BEGIN
INSE...
Razor comment syntax
...
In visual studio, select some code/markup in your razor view and press Ctrl+K, Ctrl+C, and it'll comment the selection as described above.
– MrBoJangles
Feb 17 '11 at 18:12
...
What are the disadvantages of using persistent connection in PDO
...
I hope I had read this answer before running SELECT orders.* FROM orders LEFT JOIN items USING(item_id)
– Ast Derek
Jul 26 '10 at 18:09
31
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How do I show the schema of a table in a MySQL database?
...rpreted the first way. For anybody reading the question the other way try
SELECT `table_schema`
FROM `information_schema`.`tables`
WHERE `table_name` = 'whatever';
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Get the current displaying UIViewController on the screen in AppDelegate.m
...return [UIWindow getVisibleViewControllerFrom:[((UITabBarController *) vc) selectedViewController]];
} else {
if (vc.presentedViewController) {
return [UIWindow getVisibleViewControllerFrom:vc.presentedViewController];
} else {
return vc;
}
}
}...