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What is data oriented design?
...gner will also likely split out infrequently accessed data into a separate table rather than creating a table with huge number of columns were only a few of the columns are ever used. He might also choose to denormalize some of the tables so that data don't have to be accessed from multiple location...
Google App Engine: Is it possible to do a Gql LIKE query?
...
BigTable, which is the database back end for App Engine, will scale to millions of records. Due to this, App Engine will not allow you to do any query that will result in a table scan, as performance would be dreadful for a well...
submitting a GET form with query string params and hidden params disappear
...
What you can do is using a simple foreach on the table containing the GET information. For example in php :
foreach ($_GET as $key => $value) {
echo("<input type='hidden' name='$key' value='$value'/>");
}
...
How do I modify fields inside the new PostgreSQL JSON datatype?
... TEXT,
"value_to_set" anyelement
)
RETURNS json
LANGUAGE sql
IMMUTABLE
STRICT
AS $function$
SELECT concat('{', string_agg(to_json("key") || ':' || "value", ','), '}')::json
FROM (SELECT *
FROM json_each("json")
WHERE "key" <> "key_to_set"
UNION ALL
...
SQL Server Text type vs. varchar data type [closed]
...NTEXT. You'll need to enable large value types out of row for them with sp_tableoption if you want them to be always stored out of row.
As mentioned above and here, TEXT is going to be deprecated in future releases:
The text in row option will be removed in a future version of SQL Server. Avoid usi...
How to parse JSON data with jQuery / JavaScript?
... Thank you. helpful answer. How to get specified column value in a db table ?
– PHPFan
Aug 3 '19 at 9:51
@PHPFan ...
Why does calling a method in my derived class call the base class method?
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You can imagine, that a class, when instantiated, is nothing more than a table of pointers, pointing to the actual implementation of its methods. The following image should visualize this pretty well:
Now there are different ways, a method can be defined. Each behaves different when it is used ...
.NET data structures: ArrayList, List, HashTable, Dictionary, SortedList, SortedDictionary — Speed,
....g. List<string>. Other than that, acts very much like ArrayList
Hashtable - plain old hashtable. O(1) to O(n) worst case. Can enumerate the value and keys properties, and do key/val pairs
Dictionary - same as above only strongly typed via generics, such as Dictionary<string, string>
Sor...
How do I kill all the processes in Mysql “show processlist”?
...<USERNAME> -p<PASSWORD>
mysqladmin processlist will print a table with the thread ids;
awk will parse from the second column only the numbers (thread ids) and generate MySQL KILL commands;
and finally the last call to mysql will execute the passed commands.
You can run grep before t...
Any reason to prefer getClass() over instanceof when generating .equals()?
...ke sure that your overriding implementations fully maintain the contract established by the Object class.
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