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CROSS JOIN vs INNER JOIN in SQL
...---------------------------------x
2. CROSS JOIN
Cross join selects the all the rows from the first table and all the rows from second table and shows as Cartesian product ie, with all possibilities
Consider we need to find all the teachers in the school and students irrespective of class teacher...
What's the difference between including files with JSP include directive, JSP include action and usi
...ribute to the current page at translation time. The directive was
originally intended for static layout templates, like HTML headers.
2) The <jsp:include> standard action:
<jsp:include page="header.jsp" />
Dynamic: adds the content from the value of the page attribute to...
What's with 181783497276652981 and 8682522807148012 in Random (Java 7)?
...d have worked as well as these two numbers?
Not every number would be equally "good". So, no.
Seeding Strategies
There are differences in the default-seeding schema between different versions and implementation of the JRE.
public Random() { this(System.currentTimeMillis()); }
public Ra...
What exactly do “IB” and “UB” mean?
...ned behaviour should behave. Also known as "nasal demons" because theoretically it could make demons fly out of your nose.
Using undefined behaviour is nearly always a bad idea. Even if it seems to work sometimes, any change to environment, compiler or platform can randomly break your code.
...
Random row from Linq to Sql
... select row).FirstOrDefault();
Note that this is only suitable for small-to-mid-size tables; for huge tables, it will have a performance impact at the server, and it will be more efficient to find the number of rows (Count), then pick one at random (Skip/First).
for count approach:
var qry...
Are there any smart cases of runtime code modification?
...some Unices.
Sometimes code is translated into code at runtime (this is called dynamic binary translation):
Emulators like Apple's Rosetta use this technique to speed up emulation. Another example is Transmeta's code morphing software.
Sophisticated debuggers and profilers like Valgrind or Pin u...
I want to execute shell commands from Maven's pom.xml
...a while to find this simple syntactical mistake. Maven's error output is really not that helpful.
– joergl
Aug 29 '16 at 8:23
1
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Why use symbols as hash keys in Ruby?
...saves memory, because they are only stored once.
Symbols in Ruby are basically "immutable strings" .. that means that they can not be changed, and it implies that the same symbol when referenced many times throughout your source code, is always stored as the same entity, e.g. has the same object id...
C# Ignore certificate errors?
...
Add a certificate validation handler. Returning true will allow ignoring the validation error:
ServicePointManager
.ServerCertificateValidationCallback +=
(sender, cert, chain, sslPolicyErrors) => true;
...
An explicit value for the identity column in table can only be specified when a column list is used
...ist. Thus, you have the following options:
Make a column list (either manually or using tools, see below)
OR
make the identity column in tbl_A_archive a regular, non-identity column: If your table is an archive table and you always specify an explicit value for the identity column, why do you eve...