@rolfl Can you explain what he means by "Can I make a for loop to create new touch event so I don't have to make an if statement for every new card in the discard pile (because we programmers are lazy)?" ?
That sounds a bit like advice about code not yet written
Overall I find your question very unclear, and part of it is because of a lack of context. In which method is this code? From where do you get your list of TouchEvents ? Please provide more context. — Simon André Forsberg8 secs ago
So, whether you're still in the development stages or your app is already on the app store, you always hope your app isn't crashing. But if it is, you want to be sure you've got good crash reports, right? Moreover, if your app is on the appstore, it may not be sufficient to wait around for Appl...
So, whether you're still in the development stages or your app is already on the app store, you always hope your app isn't crashing. But if it is, you want to be sure you've got good crash reports, right? Moreover, if your app is on the appstore, it may not be sufficient to wait around for Appl...
I've been using https://crackstation.net/hashing-security.htm#javasourcecode that PBKDF2 implementation for creating salted hashes and its working fine but it says I can adjust some of the variables such as:
public static final int SALT_BYTE_SIZE = 24;
public static final int HASH_BYTE_SIZE = 2...
Is my Application.php class secure for continuing development?
The Application.php acts as a registry for the whole application. I tried not to rewrite already working code that is being pulled from Zend Framework and PhalconPHP, but allow myself to have freedom with using frameworks within my w...
How can I improve this method that add data to three tables in the database? The tables are UserTable, UserInfoTable and ContactTable. UserInfoTable and ContactTable have a one to many relationship with ContactTable having UserInfoID as foreign key.
public static boolean addUser(User user) {
Con...
I have written a Python script that get status code of pages:
#!/usr/bin/python
import os
import sys
import socket
import urllib2
from urllib2 import HTTPError
if len(sys.argv) < 2:
print 'usage: python %s <file-urls>' % (sys.argv[0])
sys.exit(2)
while True:
question = raw_...
I have one complex method with 1890 paths.
I don't know, how can be this refactored. Can somebody add some tips about it?
Maybe the mysql table structure is wrong.
public function fetchClubChallengeState()
{
$c = $this->caller->in_club;
$o = $this->opponent->in_club;
if (!$c || !$o)...
I finally got my code to compile, had to edit my last question since I couldn't run it from work, had a few FOREIGN KEY constraints that didn't work quite right when I ran it from Workbench...
I started a project to build my own invoicing and management system to take the place of prohibitively expensive QuickBooks software. This will be broken down in 5 steps, with the current step in bold font, and previous steps linked.
Design the DB schema and table relationships, and insert dat...
Third normal form is the third step in normalizing a database design to reduce the duplication of data and ensure referential integrity by ensuring that
# the entity is in second normal form and
# all the attributes in a table are dependent on the primary key and only the primary key.
Definition of third normal form
The third normal form (3NF) is a normal form used in database normalization. 3NF was originally defined by E.F. Codd in 1971. Codd's definition states that a table is in 3NF if and only if both of the following conditions hold:
* The relation R (table) is in second normal form...
@Phrancis It would be nice if you could add an ER diagram to it... Even phpMyAdmin can make one for you
I have a huge list of song objects in my program and I need those objects in almost all activities. Well, at least a part of it up to everything.
So I created a class which looks pretty much like this :
class DataStore {
private static ArrayList<Song> songList;
private static ArrayList<A...
I want to implement KD tree. I have defibed class node as follows:
public static class Node{
int id;
public double x;
public double y;
public Node leftChild;
public Node rightChild;
Node(int id, double x, double y){
this.id = id;
this.x = x;
this....
You may use the following with Java 8:
String s1 = "a";
String s2 = null;
String s3 = "c";
String s4 = "d";
String concat = Stream.of(s1, s2, s3, s4)
.filter(s -> s != null)
.collect(Collectors.joining());
gives
abc
A few things to note:
You can turn data structures (lists...
@skiwi it was part former and now part latter. Workbench is acting funny. But yes, the tables were actually floating with no FK. Now Workbench is being stupid and not wanting to give me the ER, even though the code works fine
Also, that is a weird dream.
I think I had a weird dream as well, about learning Java. But I can't quite recall how it went...
Now time to start learning START TRANSACTION ... COMMIT;
Phrancis, under the covers, there's no difference between using code to begin a transaction versus using code to send a SQL command to begin a transaction.
When working with SQL transactions, it's quite important to make sure your code is guaranteed to go through a COMMIT or ROLLBACK after you've starting a transaction.
Although, despite having about as much experience in Objective-C and iOS development as I do in SQL development, I feel like I know much more about the former.
Or perhaps rather, there's much less that I don't know about the former.
When you begin a transaction, anything you touch inside the transaction is locked to anyone outside--they can't even select from the tables that you're locking up.
ROLLBACK ends the transaction, undoing any changes made within the transaction.
COMMIT ends the transaction, committing any changes made within the transaction.
Ah, okay, so it's important for data integrity that someone doesn't query these tables while data is in one but not the other.
In this case, SQL Server has a way to check if a server error has occurred
By querying @@Error I think
So you'd start the SP by beginning a transaction. After each insert, do whatever MySQL has available to see if an error happened during one of your inserts. If it did, ROLLBACK the transaction, and return out of the SP.
And ideally, your SP might take a varchar as an output argument so you can return an error reason
After the last SP, you once again check for error, this time in an if/else
and if no error, commit transaction and return out of the SP.
I guess really, it's all one reason to do a transaction.
If you're not running through multiple inserts that need to happen at the same time for data integrity purposes, you don't need a transaction most likely.
Well, either data integrity, or the possibility of some sort of error happening between the inserts.
DELIMITER |
CREATE PROCEDURE sp_AddPersonCustomerSimple
-- p_ is for parameter
(
IN p_FirstName VARCHAR(40),
IN p_LastName VARCHAR(40),
IN p_Organization VARCHAR(100),
IN p_Website VARCHAR(100),
IN p_Address VARCHAR (100),
IN p_Phone VARCHAR(20),
IN p_Email varchar(50)
)
BEGIN
START TRANSACTION READ WRITE;
BEGIN
DECLARE v_NewPerson INT;
INSERT INTO Person
(
FirstName,
LastName,
Organization,
Website,
)
I don't know that I'd need a transaction for a select statement.
Although... you can SELECT * FROM Table WITH(NOLOCK) and I believe that let's you read even if the table is in a transaction, I'm not entirely sure though
SQL Server has transaction isolation levels. (most databases do).
depending on the isolation level, different things can happen, but, by default, if you have a transaction, and select data in the transaction, during the select, nothing else can update the data
you can add a 'select for update' indicator, which will mean that the read lock will stick around until the end of the transaction, with the expectation that it will be escalated to a write lock as well.
In SQL Server, as far as I've been able to tell, if you touch a table in a transaction, by default, nothing else can do anything with the data in that table.
99% of my work is on the mobile app companion to our desktop software. The other 3 programmers work exclusively on the desktop software. This week, while looking through code for the desktop software, I found a place to make an improvement to some SQL related code.
@rolfl I would really like to see what you think about this
Also, here is a complete procedure I just got done writing. (note it assumes default values on several columns, I plan to do a more detailed one later)
DELIMITER |
CREATE PROCEDURE sp_AddPersonCustomerSimple
-- p_ is for parameter
(
IN p_FirstName VARCHAR(40),
IN p_LastName VARCHAR(40),
IN p_Organization VARCHAR(100),
IN p_Website VARCHAR(100),
IN p_Address VARCHAR (100),
IN p_City VARCHAR(40),
IN State VARCHAR(2),
IN ZipCode VARCHAR(5),
IN p_Phone VARCHAR(20),
IN p_Email varchar(50)
)
BEGIN
START TRANSACTION READ WRITE;
BEGIN
DECLARE v_NewPerson INT;
INSERT INTO Person
(
FirstName,
@Phrancis - if I may, I suggest you reorganize your SQL to put all the create-tables in one place, and all the INSERTS in to another. Posting the image from the workbench would be good too.
I think creating all the tables first makes sense. Also, while time is a very important consideration in SQL scripts, when it's something like this where you're just running it once to create the database, time is less important.
You certainly shouldn't spend a whole lot of time optimizing a create or update script.
Right, but I'd almost argue that from a clarity perspective, it almost makes more sense to have all the tables created first so I've got the bigger picture of the entire database.
Since I'm creating a whole database in one script I figured it would be easier to insert values in outer tables right then and there, rather than at the end
This may be me being sadistic, but I actually tend to prefer MySQL syntax over SQL Server syntax. It seems generally more explicit. But @rolfl is going to disagree.
One time I should set DELIMITER LOL this should make the script more lively...
So, // in C#, ' in VB.NET, and -- in SQL Server. Given that it's the same company managing all three languages, you'd think there'd be some consistency, especially considering how popular // is across other languages.
I don't know whether or not I'll be able to get to 400 ObjC points before ObjC tag starts to die in favor of Swift. Don't know how fast the transition will be.
> Time-sequence data - your Product table contains the Product cost value. Are your products going to be the same cost forever? If the cost changes, it will screw up your invoice data.....
Haha... I just talked someone into changing their accepted answer to mine
That's fine, but just consider the other answer didn't really explain the problem/solution, moreover the other answer isn't actually completely correct and wouldn't work if you just copy & pasted it over. — nhgrif5 mins ago
@nhgrif realistically I may change my prices in the future (hopefully upwards) do you think it would warrant just creating a new Product then? Any best practices on how to "label" them (for the lack of a better word)
I like @skiwi 's idea... normalize into a ProductPrice table, with EffectiveDate and ExpireDate columns, and work the logic in based on Invoice.InvoiceDate
More specifically: That allows writing the database as 'proper' (normalized) as possible, yet also giving the option to 'dynamically' trade in normalization for performance.
Phrancis, if you join like that, you will absolutely have to put a trigger on your price table to make certain that the effective/expire dates can't overlap for a given product.
Tweebuffelsmeteenskootmorsdoodgeskietfontein is a farm in the North West province of South Africa, located about 200 km west of Pretoria and 20 km east of Lichtenburg whose 44-character name has entered South African folklore. The name was used as the title for an Afrikaans lyric written by and performed by Anton Goosen.
The name, which follows a common format for place names in South Africa, is Afrikaans for "The spring where two buffaloes were cleanly killed with a single shot". The literal translation is "Twee buffels" = "Two buffaloes", "met een skoot" = "with one shot";...
2
Two buffalo mortally shot with one bullet near a spring.
SET TRANSACTION LEVEL READ UNCOMMITTED is probably the best performing, but then it potentially could compromise normalization as far as your result set is concerned
I have class point that represents point in 2D and I want to sort these points once based on their x-coordinate and second based on their y coordinate. Since x and y are double values my code looks like this:
public static class Point{
int id;
public double x;
public double y;
Po...
In my experience, it's not always easy to predict what operations are actually going to be expensive. You just test it out. If it's too expensive, then you try to figure out how to make it less expensive.
My onions are not very savvy about CPUs. But they sure do taste good.
@nhgrif sure but some operations, you can tell just by looking at them that they are going to be expensive... I once saw a script with a self JOIN and SELECT DISTINCT * that took over 30 mins to execute
There's also "How much faster can I make this?" versus "How much of a time investment is there in order to make this faster?"
If it takes a week of work to improve a 4 second query down to 3 seconds, is it worth it?
And added to that is, how much more complex is the new query? Does it's higher efficiency come at the cost of readability/maintainability? And again, is that worth it?
We have a stored procedure that runs overnight when no one is using the server. It used to take 6 hours to run, but the lead programmer has gotten it down to under 30 minutes.
So, whether you're still in the development stages or your app is already on the app store, you always hope your app isn't crashing. But if it is, you want to be sure you've got good crash reports, right? Moreover, if your app is on the appstore, it may not be sufficient to wait around for Appl...
I've been using https://crackstation.net/hashing-security.htm#javasourcecode that PBKDF2 implementation for creating salted hashes and its working fine but it says I can adjust some of the variables such as:
public static final int SALT_BYTE_SIZE = 24;
public static final int HASH_BYTE_SIZE = 2...
I have written a Python script that get status code of pages:
#!/usr/bin/python
import os
import sys
import socket
import urllib2
from urllib2 import HTTPError
if len(sys.argv) < 2:
print 'usage: python %s <file-urls>' % (sys.argv[0])
sys.exit(2)
while True:
question = raw_...
I have one complex method with 1890 paths.
I don't know, how can be this refactored. Can somebody add some tips about it?
Maybe the mysql table structure is wrong.
public function fetchClubChallengeState()
{
$c = $this->caller->in_club;
$o = $this->opponent->in_club;
if (!$c || !$o)...
I want to implement KD tree. I have defibed class node as follows:
public static class Node{
int id;
public double x;
public double y;
public Node leftChild;
public Node rightChild;
Node(int id, double x, double y){
this.id = id;
this.x = x;
this....
You may use the following with Java 8:
String s1 = "a";
String s2 = null;
String s3 = "c";
String s4 = "d";
String concat = Stream.of(s1, s2, s3, s4)
.filter(s -> s != null)
.collect(Collectors.joining());
gives
abc
A few things to note:
You can turn data structures (lists...
