I am re-designing a service so that large data sets can searched using BigQuery. Originally, I was going to set up a process to stream data from CloudSQL to BigQuery each evening but I became aware of federated queries during the research phase. Perhaps I missing something obvious but I cant seem to find anything that specifically notes if BigQuery federated queries are as performative as normal BigQuery queries. It seems to focus on the problem of storing data in multiple systems and federated queries making it easier to join MySQL (or Postgres) data with BigQuery data.
Do federated queries leverage all or most of the advantages of BigQuery (using thousands of machines to perform scans) or is that not possible? Google says "*May not perform as well as querying data residing in BigQuery tables" but has anyone used this and found it to be close to or similar?
The performance is limited to your CloudSQL instance's capacity. That's your bottleneck.
For sure you already read this but gathering the information from different sections you can see that what actually happens is the following.
BigQuery will send a query to be executed at your CloudSQL instance.
The results of the query will be read by BigQuery and stored in a temporary table.
Keep in mind, this means you are putting some load in your CloudSQL instance, and also you need to read bytes (and pay for them) in BigQuery.
This is clearly different from using one of the commercial tools like StitchData or Fivetran to replicate your CloudSQL data in BigQuery and then querying it directly in BigQuery.
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Looking for suggesting on loading data from SQL Server into Elasticsearch or any other data store. The goal is to have transactional data available in real time for Reporting.
We currently use a 3rd party tool, in addition to SSRS, for data analytics. The data transfer is done using daily batch jobs and as a result, there is a 24 hour data latency.
We are looking to build something out that would allow for more real time availability of the data, similar to SSRS, for our Clients to report on. We need to ensure that this does not have an impact on our SQL Server database.
My initial thought was to do a full dump of the data, during the weekend, and writes, in real time, during weekdays.
Thanks.
ElasticSearch's main use cases are for providing search type capabilities on top of unstructured large text based data. For example, if you were ingesting large batches of emails into your data store every day, ElasticSearch is a good tool to parse out pieces of those emails based on rules you setup with it to enable searching (and to some degree querying) capability of those email messages.
If your data is already in SQL Server, it sounds like it's structured already and therefore there's not much gained from ElasticSearch in terms of reportability and availability. Rather you'd likely be introducing extra complexity to your data workflow.
If you have structured data in SQL Server already, and you are experiencing issues with reporting directly off of it, you should look to building a data warehouse instead to handle your reporting. SQL Server comes with a number of features out of the box to help you replicate your data for this very purpose. The three main features to accomplish this that you could look into are AlwaysOn Availability Groups, Replication, or SSIS.
Each option above (in addition to other out-of-the-box features of SQL Server) have different pros and drawbacks. For example, AlwaysOn Availability Groups are very easy to setup and offer the ability to automatically failover if your main server had an outage, but they clone the entire database to a replica. Replication let's you more granularly choose to only copy specific Tables and Views, but then you can't as easily failover if your main server has an outage. So you should read up on all three options and understand their differences.
Additionally, if you're having specific performance problems trying to report off of the main database, you may want to dig into the root cause of those problems first before looking into replicating your data as a solution for reporting (although it's a fairly common solution). You may find that a simple architectural change like using a columnstore index on the correct Table will improve your reporting capabilities immensely.
I've been down both pathways of implementing ElasticSearch and a data warehouse using all three of the main data synchronization features above, for structured data and unstructured large text data, and have experienced the proper use cases for both. One data warehouse I've managed in the past had Tables with billions of rows in it (each Table terabytes big), and it was highly performant for reporting off of on fairly modest hardware in AWS (we weren't even using Redshift).
I am Asp.Net MVC/SQLSERVER developer and I am very new to all these and so I may be on compelete wrong path.
I came to know by googling that Snowwflake can put/get data from AWS-S3, Google Storage and Azure. And Snowflake has their database and tables as well.
I have following questions,
Why one should use Snowflake when you can compute your data with Cloud Storage(S3 etc) and Talend or any other ETL tool?
Can we use Snowflake as database for data driven web application? and if yes, could you provide link or something to start?
Once again I am very new to all these and expecting from you to get ideas and best way to work arround this.
Thak you in advance.
Why one should use Snowflake when you can compute your data with Cloud Storage(S3 etc) and Talend or any other ETL tool?
You're talking about three different classes of technology product there, which are not equivalent:
Snowflake is a database platform, similar to other database technologies it provides data storage and metadata and a SQL interface for data manipulation and management.
AWS S3 (and similar products) provides scalable cloud storage for files of any kind. You generally need to implement an additional technology such as Spark, Presto, or Amazon Athena to query data stored as files in cloud storage. Snowflake can also make use of data files in cloud storage, either querying the files directly as an "external table" or using a COPY statement to load the data into Snowflake itself.
Talend and other ETL or data integration tools are used to move data between source and target platforms. Usually this will be from a line of business application, such as an ERP system, to a data warehouse or data lake.
So you need to think about three things when considering Snowflake:
Where is your analytical data going to be stored? Is it going to be files in cloud storage, loaded into a database or a mix of both? There are advantages and disadvantages to each scenario.
How do you want to query the data? It's fairly likely you'll want something that supports the use of SQL queries, as mentioned above there are numerous technologies that support SQL on files in cloud storage. Query performance will generally be significantly better if the data is loaded into a dedicated analytical database though.
How will the data get from the data sources to the analytical data repository, whatever that may be? Typically this will involve either a third party ETL tool, or rolling your own solution (which can be a cheaper option initially but can become a significant management and support overhead).
Can we use Snowflake as database for data driven web application?
The answer to that is yes, in theory. It very much depends on what your web application does because Snowflake is a database designed for analytics, i.e. crunching through large amounts of data to find answers to questions. It's not designed as a transactional database for a system that involves lots of updates and inserts of small amounts of data. For example Snowflake doesn't support features like referential integrity.
However, if your web application is an analytical one (for example it has embedded reports that would query a large amount of data and users will typically be reading data and not adding it) then you could use Snowflake as a backend for the analytical part, although you would probably still want a traditional database to manage data for things like users and sessions.
You can connect your web application to Snowflake with one of the connectors, like https://docs.snowflake.com/en/user-guide/odbc.html
Snowflake excels for large analytic workloads that are difficult to scale and tune. If, for example, you have many (millions/billions) of events that you want to aggregate into dashboards, then Snowflake might be a good fit.
I agree with much of what Nathan said, to add to that, from my experience every time I've created a database for an application it's been with an OLTP database like PostgreSQL, Azure SQL Database, or SQL Server.
One big problem of using MPP/Distributed Databases is that they don't enforce referential integrity, so if that's important to you then you don't want to use MPP/Distributed Databases.
Snowflake and other MPP/Distributed Databases are NOT meant for OLTP workloads but instead for OLAP workloads. No matter what snake oil those companies like databricks and snowflake try to sell you MPP/Distributed databases are NOT meant for OLTP. The costs alone would be tremendous even with auto-scaling.
If you think about it, Databricks, Snowflake, etc. have a limit to how much they want to optimize their platforms because the longer a query runs the more money they make. For them to make money they have to optimize performance but not too much otherwise it will effect their income.
This can be an in-depth topic so I would recommend doing more research into OLTP Vs. OLAP.
Enforcing Referential integrity is a double edged sword, the downside being as the data volume grows the referential violation check significantly slows down the inserts and deletes. This results in the developer having to put the RI check in the program (with a dirty read) and turn off the RI enforcement by the database, finally ending up with a Snowflake like situation.
Bottom line is Snowflake not enforcing RI should not be a limitation for OLTP applications.
I'm using a Cloud SQL instance to store two types of data: typical transactional data and large "read-only" data. Each of these read-only tables could have GBs of data and they work like snapshots that are refreshed once a day. The old data is totally replaced by the most recent data. The "read-only" tables reference data from the "transactional tables", but I don't necessarily need to perform joins between them, so they're kind of "independent".
In this context, I believe using Cloud SQL to store these kind of tables are going to be a problem in terms of billing. Because Cloud SQL is fully managed, I would be paying for maintenance work from Google and I wouldn't need any kind of maintenance for those specific tables.
Maybe there are databases more suitable for storing snapshot/temporary data. I'm considering to move those type of tables to another kind of storage, but it's possible that I would end up making the bill even higher. Or maybe I could continue using Cloud SQL for those tables and just unlog them.
Can anyone help me with this? Is there any kind of storage in GCP that would be great for storing large snapshots that are refreshed once a day? Or is there an workaround to make Cloud SQL not maintain those tables?
This is a tough question because there are a lot of options and a lot of things that could work. The GCP documentation page "Choosing a Storage Option" is very handy in this kind of cases. It has a flowchart to select a storage option based on the kind of data you want to store, a video that explains each storage option and a table with the description, strong points and use cases for each option. I would recommend to start there.
Also, if the issue with Cloud SQL is that is fully managed and pricy, you can set up MySQL on Google Compute Engine and manage it yourself. Is also fairly cheaper for the same machine. For a n1-standard-1, $0.0965 in Cloud SQL and $0.0475 in GCE (keep in mind that other charges may apply on top of the machine price)
In my company we have multiple database structure hosted in SQL Server.
for e.g., whenever a new customer sign up with us, we create a new DB in SQL Server to maintain their data.
Right now we already have 2000+ DBs in our database server. We expect more customers to sign up in near future, which might even cross 5000+ count.
Having DBs of 5000+ and increasing count of DBs might not be an advisable one, sometimes we run some task which will run across the DBs, and if we are going to run tasks across 5000+ DBs we will surely end up in performance issues.
What would be the alternative solution to avoid creating multiple DBs for each and every customer and also at the same time maintaining their data separately?
I am hearing about BigData and other DataBase solutions but could not get clear picture.
Can someone share some light on this?
If the databases have an identical schema you could combine them into one. That way each customer's table will now become a set of rows in the new database. A new customer will probably be a few new rows in the tables that store customer's profile.
You can use row level security for restricting access to customer's data:-
https://msdn.microsoft.com/en-us/library/dn765131.aspxpx
For pros and cons of using this approach over your existing see: Pros/Cons Using multiple databases vs using single database and Single or multiple databases
Using other options provide great learning opportunity but may have a significant transition cost even if there were some that were indeed better.
one solution I would suggest is to use prefix on the table name for each customer. you can then solve the security issue by limit per customer per set of tables.
the con is you will have to rewrite your application to use prefix to each table whenever it want to access it. If you have a lot of tables , that will be a problem.
I think this is how some multi Wordpress hosting site handle it database issue.
you should consider if you just store the data and access it with simple querys or if you usually do complex query's, if you just store the data and access it with simple querys and your need are not 100% relational maybe you should consider to move part of your data to HDFS file system:
https://en.wikipedia.org/wiki/Apache_Hadoop#HDFS .
To process the data in hadoop there are many tools but the raising one for sure is spark:
https://en.wikipedia.org/wiki/Apache_Spark
probably the best solution is to start move your historic data in HDFS just for storage and keep the rest as it is until you take confidence with the hadoop and spark paradigm
hadoop is a distributed , fault tollerant file system and spark is an engine for batch processing huge amount of unstructured or structured data, consider that data in hadoop are not structure usually so you have to change the way you process your data, if you want to still use sql I suggest to check Impala and Hive as well:
http://impala.io/
https://hive.apache.org/
Take a look at cloudera web site for a more structure IT solution instead of a lot of single tool that you will need to organize
http://www.cloudera.com/content/www/en-us/solutions.html
They have a quick start VM to try all the hadoop ecosystem tools , probably thats the best way to start experimenting:
http://www.cloudera.com/content/www/en-us/downloads/quickstart_vms/5-4.html
what database to choose to store information about site visits, key characteristics: big amount of data, many page requests per second, different reports for data presentation, i think to use MySql, any suggestions?
Consider letting the server log the requests and parsing them asynchronously. You don't need ACID for analytics, and you don't need to process them while talking to a client.
Most mainstream databases are good for that (including mysql, postgres, oracle etc). MySql is fine though, especially if you've used it before.
Be sure look at licenses as well: MySql is GPL (the database and the connectors), Postgres is BSD, Oracle (and a few others) you need to pay for.
Most web analytics companies use some kind of distributed file system to store logs, such as HDFS, QFS... The reason is that the data is too big for the traditional database.
Analytics reports are generated via MapReduce job.
If you want to do an adhoc query, you normally use something like Hive/Pig/Sawzall.