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Why is early return slower than else?
...ashing works:
__builtins__ hashes to -1196389688 which reduced modulo the table size (32) means it is stored in the #8 slot of the table.
without_else hashes to 505688136 which reduced modulo 32 is 8 so there's a collision. To resolve this Python calculates:
Starting with:
j = hash % 32
perturb ...
Why is LINQ JOIN so much faster than linking with WHERE?
...nce they work directly in memory (Linq to DataSet)
The query with multiple tables and a Where condition actually performs a cartesian product of all the tables, then filters the rows that satisfy the condition. This means the Where condition is evaluated for each combination of rows (n1 * n2 * n3 * ...
Set default value of an integer column SQLite
...
Use the SQLite keyword default
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " ("
+ KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_NAME + " TEXT NOT NULL, "
+ KEY_WORKED + " INTEGER, "
+ KEY_NOTE + " INTEGER DEFAULT 0);");
This link is useful: ht...
UITableview: How to Disable Selection for Some Rows but Not Others
I am displaying in a group tableview contents parsed from XML. I want to disable the click event on it (I should not be able to click it at all) The table contains two groups. I want to disable selection for the first group only but not the second group. Clicking the first row of second group nav...
Creating and Update Laravel Eloquent
...built in L4 functionality for doing this in some way such as:
$row = DB::table('table')->where('id', '=', $id)->first();
// Fancy field => data assignments here
$row->save();
I did create this method a few weeks back...
// Within a Model extends Eloquent
public static function creat...
What are file descriptors, explained in simple terms?
...file in operating system.
If your process opens 10 files then your Process table will have 10 entries for file descriptors.
Similarly when you open a network socket, it is also represented by an integer and it is called Socket Descriptor.
I hope you understand.
...
Warning: Null value is eliminated by an aggregate or other SET operation in Aqua Data Studio
... solve this problem?. How to change the null data to 0 when no data in the table?.
6 Answers
...
What's the Hi/Lo algorithm?
...re out the next identifier value knowing we use hilo in this particular DB table?
– Vlad Mihalcea
Feb 7 '17 at 1:46
My...
Remove duplicated rows
...
The data.table package also has unique and duplicated methods of it's own with some additional features.
Both the unique.data.table and the duplicated.data.table methods have an additional by argument which allows you to pass a chara...
Keeping it simple and how to do multiple CTE in a query
I have this simple T-SQL query, it emits a bunch of columns from a table and also joins information from other related tables.
...