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Is String.Contains() faster than String.IndexOf()?
I have a string buffer of about 2000 characters and need to check the buffer if it contains a specific string.
Will do the check in a ASP.NET 2.0 webapp for every webrequest.
...
how to use ng-option to set default value of select element
I've seen the documentation of the Angular select directive here: http://docs.angularjs.org/api/ng.directive:select .
I can't figure how to set the default value. This is confusing:
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How to disable/enable select field using jQuery?
...gt;
<label for="pizza">I would like to order a</label>
<select id="pizza_kind" name="pizza_kind">
<option>(choose one)</option>
<option value="margaritha">Margaritha</option>
<option value="hawai">Hawai</option>
</select>
...
Is there a goto statement in Java?
...
@mwieczorek Not all. "char" is a primitive type and it's unsigned.
– Sergey Krivenkov
Nov 20 '18 at 9:47
add a comment
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Fast way to discover the row count of a table in PostgreSQL
...in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like this (extremely fast):
SELECT reltuples::bigint AS estimate FROM pg_class where relname='mytable';
How close the estimate is depends on ...
How does a hash table work?
...but strong hashing...
size_t random[8][256] = { ...random data... };
const char* p = (const char*)&my_double;
size_t hash = random[0][(unsigned)p[0]] ^
random[1][(unsigned)p[1]] ^
... ^
random[7][(unsigned)p[7]];
Weak but oft-fast hashing...
Many librar...
DISTINCT for only one column
...
If you are using SQL Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ...
How to request a random row in SQL?
...
See this post: SQL to Select a random row from a database table. It goes through methods for doing this in MySQL, PostgreSQL, Microsoft SQL Server, IBM DB2 and Oracle (the following is copied from that link):
Select a random row with MySQL:
SELE...
How do I run a batch file from my Java Application?
... int i = 0;
while( (i = is.read() ) != -1) {
System.out.print((char)i);
}
} catch(IOException ioException) {
System.out.println(ioException.getMessage() );
}
share
|
improve thi...
PostgreSQL return result set as JSON array?
...
TL;DR
SELECT json_agg(t) FROM t
for a JSON array of objects, and
SELECT
json_build_object(
'a', json_agg(t.a),
'b', json_agg(t.b)
)
FROM t
for a JSON object of arrays.
List of objects
This section de...