I am kind of a amateur at web development. But it seems like most people develop on their local machines and the upload to their remote servers when everything is ready. I want to start doing this. I've installed Xampp (Apache) on my local machine. But in order for this to really work, i need the the mysql databases that already exist on my remote server to be "synched" or "duplicated" on my local machine. But I'm finding this somewhat hard to figure out.
First, Should I be using mysql "reduplication" feature (with my remote server as master) and local machine as slave? Or is there a better way to do this? Should I be synchronizing instead of reduplicating
Second, Is anyone willing to give me a quick description of how I achieve this "reduplication" or "synchronization"
Thanks
It may be tempting, but it's hopeless to try to keep the database in two places. Instead, always keep the database on the server because it's much easier to develop and debug your code if it's in just one place. "Resynch" and "reduplicate" and all that business is just too much trouble, as you are discovering. The DB is going to end up on the server anyway, so you may as well put it there right now.
Also, you will not need a web server on your local machine, which will unburden you.
This next is applicable if you are writing CGI. If you aren't sure whether or not you are writing CGI, then you are not (well, probably not). {
If you mainain just one database and it lives on your server, you'll be able to write one piece of portable code that will run equally well on your local machine and on your server. This is a huge win, take my word for it.
To get this working, you will need the mysql library on your local machine; no other mysql component is needed there. The mysql server will run on your server only.
Read up on mysql "connector" for the language you're using.
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Related
I am working at a company that has some CRM software running in a remote Windows XP server that uses a SQLAnywhere 9 db to store its data; I have access to this remote server with an administrator account.
I would like to extract the db into a .sql file so that I can run the db locally on my machine without affecting the running db in the server (since it is key for the company's day to day operation).
The reason I need this is that we are going to test some BI Software and we need data from this database to test it, but we don't know the structure of the database since the developers of the CRM software didn't give us any documentation on it. So we need to have the database locally so that, without affecting the running CRM, we can:
understand the structure by looking at the DDL
make queries to it to get sample data
I researched a bit, and the most common solution to my problem was to use dbunload on the remote server to unload the db into a reload.sql file that contained what I needed. But most tutorials on the subject mention that I have to stop the db first (which would be catastrophic). If this is the only option, then I guess I am willing to do it on the weekend when the CRM is not used, but I wanted to know if there was another solution first.
If there is no other solution, can you point me to where I can find the proper and safer way to do this?
I have researched a lot, but prior to this day I have never even heard of SQLAnywhere, so I really need all the help I can get. My main concern is doing something that impacts negatively the CRM software.
Thank you.
You can run dbunload across the network, you just have to tell it to do an "external" unload. The default is to do an internal unload which would only work from the machine where the database server is running.
I don't have SQL Anywhere 9 documentation right now to look up the exact switch, but dbunload -? should show you all the possible switches.
Edit:
-an will create a new database and load the data and schema from another data
-xi switch will do external unload and internal reload.
-c parameters to connect to your remote database
I am new to Database programming and there is some general questions that I would like to ask. I created the schema in my localhost using mySQL and linked to eclipse. There are some problems that I do not know how to approach.
One of my friends would like to help to develop at his personal machine, but he could not link to my database server. So one way is to copy the schema to his mySQL and change the connection string, are there any better ways?
If I would to release the project and run it on different machines, will it affect the databases operation since the schema resides in my local server.
Is there ways to just like attach the database inside the project since it is a local database and I am not accessing it from any other programs.
Sorry if my questions sound very stupid. I am really new.
Your approach of running local test MySQL instance for every developer sounds fine.
However, if your application never needs any data shared (essentially database is always local as you stated), then you should ask yourself if MySQL really an appropriate solution for your application. I think SQLite is a better choice in that situation - it is likely to work faster than MySQL for local access, and it has essentially zero setup - no database daemon to run or anything like that which greatly simplifies application install.
Granted, SQLite has its limits, but I often use SQLite for my projects, and only if they grow large, I might migrate them to MySQL or PostgreSQL if task requires it.
Typical signs that SQLite may not cut it:
Many clients (10+) need to access database for writing
Total database size is very large - more than 10GB total
It's one of those cases where you have a desktop application and its database is in a remote server. In my case, it's MySQL and the application is made in Delphi XE3. But when client wants his data both offline and online (for speed and security) we need to:
Login with remote server information (more updated);
Sync the online database to offline;
Do the tasks on the application and the database;
Sync back the offline database with online.
My question: Is there a standard way to do that, by MySQL instructions or another automatic way? Or Am I going to code all the rules to make it possible?
Luckily there is no need for code here.
Replication has been built into MySQL for many years.
The trick is to setup the remote host as master and the local copy as slave.
All updates go to the master.
And the slave reads from the remote.
The documentation is here: http://dev.mysql.com/doc/refman/5.7/en/replication.html
Here's a tutorial: http://www.howtoforge.com/mysql_master_master_replication
Note that there can really only be one master, if not the setup will get too complicated to be workable.
You could look at client data sets (as you need to update the local version I do not believe that mysql allows multiple masters). Basically your application connects to mysql when it is online and if your application goes offline you store the database and changes in a local xml database. One back online, you apply the updates. Downsides of cds are.: no sql locally and your local changes might conflict with changes made by other users so the apply updates must include logic to reconcile the conflicts. Also cds is involved still trying to get my head around it
I'm trying to migrate a web site to friend's server. The site uses MySQL, but he didn't previously have it set up. He's installed the package now and suggested that I could run my own instance of it. I'm at a loss for how to do so. Is it even possible? If so, how?
Some relevant information:
The OS in use is CentOS 5.9
Using MySQL 5.0.95
I only need the DB to be read locally via PHP when serving my site.
I have no root privileges on this system (although a full shell), but am close friends with the owner/administrator if that's necessary.
To clarify:
It's the daemon that I want to run my own instance of. So I guess what I want to know is if it's possible to have multiple users on the system running their own instances of mysqld containing different databases.
All I need this for is serving a web page. If I have to break down and switch to a pseudo-database using CSV files I will, but I'd much rather stick to MySQL if I can.
If MYSQL is setup on that machine yes you can run your own instance of it.
You can have it set up and your site given its on Database within that MYSQL instance and that specific MYSQL account can be used to access the tables etc. involved with your website.
Now if he is only putting MYSQL on the machine then having you set everything up you will just need an account for MYSQL and from ther eyou can get in and just create all the needed items that will allow your site to fully function.
EDIT
In response to your comment. You can you just can't clog the same port or have configurations that conflict each other. As long as it won't be to much of a performance hit and you configure a different user to start each instance you should be able to do Something like this.
I'm developing an app which will have a central database users can add entries to. The database will have to be on a server somewhere but I want the users to be able to add entries offline. The app will sync to the main db when connection is available. So, I supose I need 2 databases - the main one sitting on a server (preferably linux) and a small one on each client machine to use as a buffer when offline. The app will be coded in c# for windows. I'm having trouble deciding what databases to use and whether I can leverage any replication technology to make this easier. Also, I don't want to pay for anything ;) So I guess my questions are...
Will I have any trouble writing code in ADO.NET to move data from something like SQL Compact Edition to MySQL?
Are there any replication solutions which will move stuff from local to main database for me
I've recently discovered IBM's db2 expressC but I'm not sure if it's serverless as well as server installed. Does anyone know?
Firebird can be server or serverless. Can I replicate between them. Is the server mode capable of heavy use?
Firebird can be server or serverless.
Can I replicate between them.
Yes.
Is the server mode capable of heavy
use?
Define 'heavy use'. I've had production systems with 200 simultaneous users pumping 20 transactions/minute each on databases in the 10-20GB range. I'm sure there are many larger deployments out there.
Also, what you describe seem like the 'briefcase model'. You should look into it if you haven't already done so. Maybe the solution is not replication at the database level, but rather a smarter fat client.
Just answering two of your questions; I don't know about DB2 or Firebird.
Will I have any trouble writing code in ADO.NET to move data from something like SQL Compact Edition to MySQL?
That should be very trivial; install MySQL Connector/NET and you're good to go.
Are there any replication solutions which will move stuff from local to main database for me
SQL Server replication is made for this, but I don't suppose it would work with MySQL.