Use of CacheLoader and CacheWriter in Gemfire - gemfire

I have a client server topology in gemfire. I want to use cacheLoader and cacheWriter to synchronize my in memory gemfire cache with RDBMS database oracle.
Where exactly I should plug in these cacheLoader and cacheWriter..in the client regions or server regions or I can choose any one of these?

I would say the server regions. There's no reason why the client app should depend on an RDBMS in this case.

Related

Trigger Based Replication (Live Sync) OR Transactional Replication in MSSQL

can someone give me a clear idea about which technique/ method is more reliable, less memory consuming and faster in replicating data from one Database to another in MSSQL database(SQl Server 2012) and why. We are in the process of developing a Live GPS based tracking application and I am confused with which method to proceed with
Trigger Based Replication (Live Sync)
(OR)
Transactional Replication
Thanks in Advance ☺
I would recommend using standardised solutions whenever possible. Within the choice given to you, transaction replication should be an obvious favourite, because:
It doesn't require any coding and can be deployed using standard tools. This makes it much faster to deploy and maintain - any proper DBA can do it, some of them even being blindfolded.
Actual data transfer is done by replication agents which are separate applications external to the SQL Server process and client connections. Any network issues within the publisher-distributor-subscriber(s) chain will lead to delays in copying the data, but they will not affect the performance of the publisher database itself.
With triggers, you have neither of these advantages: you will have to add a lot of code, and sluggish network will make data-changing queries slower, potentially leading to timeouts.
Of course, there are many more ways to move the data between the databases in SQL Server, such as (in no particular order):
AlwaysOn Availability Groups (Database mirroring);
Log shipping;
CDC (Change Data Capture);
Service Broker.
However, given your needs, transaction replication still looks like your best bet, overall.

How to transfer Data from One SQL server to another with out transactional replication

I have a database connected with website, data from website is inserting in that Database, i need to transfer data from that database to another Primary Database (SQL) on another server in real time (minimum latency).
I can not use transactional replication in this case. What are the other alternates to achieve this? Can i integrate DataStreams like Apache kafka etc with SQL server?
Without more detail it's hard to give a full answer. There's what's technically possible, and there's architecturally what actually makes sense :)
Yes you can stream from RDBMS to Kafka, and from Kafka to RDBMS. You can use the Kafka Connect JDBC source and sink. There are also CDC tools (e.g. Attunity, GoldenGate, etc) that support integration with MS SQL and other RDBMS)
BUT…it depends why you want the data in the second database. Do you need an exact replica of the first? If so DB-DB replication may be a better option. Kafka's a great option if you want to process the data elsewhere and/or persist it in another store. But if you just want MS SQL-MS SQL…Kafka itself may be overkill.

Same hardware cluster

If I have two databases and views in one in which both databases are JOIN'ed or UNION'ed is this an issue for for GCSql? This feature according to MySQL only requires that both databases remain within the same hardware cluster.
I am not totally clear on what constitutes a hardware cluster, but how does that relate to google SQL instances, etc?
Each Google Cloud SQL instances has a single MySQL instance at any one time. The data is replicated to multiple locations when that single MySQL instance writes it to persistent storage -- this means that the instance can failover to a new location if there is a problem.
There isn't any hardware clustering in the sense used here.

SQL Mirroring or Failover Clustering VS Azure built in infrastructure

I read in a few places that SQL Azure data is automatically replicated and the Azure platform provides redundant copies of the data, Therefore SQL Server high availability features such as database mirroring and failover cluster aren't needed.
Has anyone got a chance to investigate deeper into this? Are all those availability enhancements really not needed in Azure? Thanks!
To clarify, I'm talking about SQL as a service and not a VM hosted SQL.
The SQL Database service (database-as-a-service) is a multi-tenant database service, and your databases are triple-replicated within the data center, providing durable storage. The service itself, being large-scale, provides high availability (since there are many VMs running the service itself, along with replicated data). Nothing is needed in terms of mirroring or failover clusters. Having said that: If, say, your particular database became unavailable for a period of time, you'll need to consider how you'll handle that situation (perhaps sync'ing to another SQL Database, maybe even in another data center).
If you go with SQL Database (DBaaS), you'll still need to work out your backup strategy, and possibly syncing with another DC (or on-premises database server) for DR purposes.
More info on SQL Database fault tolerance is here.
Your desired detail is probably contained in this MSDN article of Business Continuity and Azure SQL Database (see: http://msdn.microsoft.com/en-us/library/windowsazure/hh852669.aspx). At the most basic level Azure SQL Database will keep three replicas of your database - one primary and two secondary.
While this helps with BCP / DR scenarios you may also wish to investigate ways to backup your database so you have point-in-time restore capabilities. More information on backup / restore can be found here: http://msdn.microsoft.com/en-us/library/windowsazure/jj650016.aspx

Online and local sql database synchronization

According to my system i have maintained two databases in LAN and online db.But i want to synchronize these two databases. I hope to do this things using microsoft sync frame work.
.http://msdn.microsoft.com/en-us/library/ee819079.aspx
Can i do sync local and online sql db using this? or any suitable method for do this.thank you
Sync Framework is designed for occasionally connected systems, eg. a laptop that can access the corporate network every other day and update its database, but needs to work when it has no corpnet access too. The pairing of Sync Framework is usually a central DB (SQL Server) and local embedded SQL Server Compact or SQL Express on the devices (laptops, phones, tablets etc).
IF the databases are always connected (eg. two DBs in two servers, with 24x7 connectivity between them, even if over Internet) then the appropriate technology is replication. Either Merge or Transactional. Theoretically replication also works when disconnect periods are expected, but Sync Framework is much better at it, and most importantly Sync Framework is not strongly dependent on DNS names as replication is (very important for occasionally connected systems).
Synchronizing the database is a vague term, you have to consider if you want a Master-Slave replication shcme or a Master-Master (the later being very difficult to achieve) and you have to consider what do you want replicated from the database. You also need to consider if more partners will be later added (more databases to 'synchronize'). And you have to be way more careful now about schema changes.