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5

What you are seeing on net is mostly a copied advise where people actually want to say that "please don't make shrinking data file or log file a daily routine operation". Had it been so bad Microsoft would have removed it but it is still there and even most experienced DBA's and developer use it but they are aware about the after affects so they know what to ...


4

Having done this type of project before, here's some of the practical gotchas to look out for: "2. This master then does one-way slave propagation to up to 200 read-only servers via VPN." Think carefully about the network traffic required here. In the simplest terms, if the insert/update/delete load on the database takes up 1/200th of a network cable's ...


4

The major differences are related to duplicate entries in both data and metadata, and the existence of NULL values. SQL implementations deviate from the relational model for practical reasons, for the most part. Read up on the topic in SQL and Relational Theory by C.J. Date or (Kudos to Bill Karwin for this title by the same author) read pages 2 and 3 in ...


4

It's a good pick to use it? If I was hired on a new company, it's a good pick to use maintenance plan ( for me, looks like too "simple", don't want to look a bad DBA). Maintenance plans are not bad, but when your environment grows, the limited flexiblity and functionality that maintenance plans provide wont be sufficient. For e.g Maintenance plans ...


4

You haven't really given us much info about what this data is going to be used for. I mean, you have said what data is going to be stored, but what are you going to do with it? If your purpose is storing the data then reporting on it, then I think you're looking in the wrong place. A simple MySQL or SQL Database would do just fine and the reporting tools ...


4

Your existing index on DATE is obviously useless for the query. The first obvious step for your query: SELECT * FROM tbl WHERE column_a = 'value1' AND column_b = 'value2'; is an index for column_a or column_b (which ever is more selective) or possibly a multicolumn index on (column_a, column_b), like: CREATE INDEX tbl_a_b_idx ON tbl(column_a, column_b); ...


3

Shrinking database log file is necessary if log has grown out of control whether after a one-time data delete or where recovery model of the database is FULL and no log backups have been carried out. To reverse the effect of a one-time operation that caused unexpected log file growth are convincing reasons for shrinking a database\ database file. ...


2

If all you want to do is keep track of which authors contributed to which papers, then all you need is a simple intersecting entity (see more) like this: Here the columns of the SUBMISSION table are just the two primary key columns from PAPER and AUTHOR. These two columns will jointly form the primary key of the intersecting table and will also each ...


2

InnoDB log files are stored on disk and so consume disk space - http://dev.mysql.com/doc/refman/5.5/en/innodb-configuration.html. However the innodb_buffer_pool_size does impact memory usage. I find this a good reference for memory sizing - http://www.mysqlcalculator.com/


2

PostgreSQL comes to my mind. You have pgcrypto library for encrpyting data and there are drivers for .Net


2

The actual costs are difficult to quantify as they are often diffused. Often they appear as slower transactions. For a system used rarely, this may not be significant. For a system used for an hour a day, that is taking twice as long as is required the cost would be about 100 hrs a year per person using the system. Slower transactions may also have ...


2

My largest obstacle right now with Cassandra are the no-join, no order by (since everything is ordered by key for you), and mass update. If your current data structure depends on joins (or aggregation) to pull off the queries you need you won't find a nosql option that includes these. You do have some options: Consider reviewing your current data ...


2

For your use case of key-value data, where the value is simple, MongoDB is more than you need. It is a document-oriented data store for complex value types. A specific key-value store would suit your needs. RIAK is the one I've looked at though several others exist. Since your retrieval will be by time range i.e. key range, Elastic's full-text ...


2

Generally speaking I would recommend a full fledged relational database. This will give you everything you need, and allow you to grow gracefully. As far as what exact engine to use that depends on personal preference/budgetary constraints/hosting requirements/compatability with the application layer/etc. Personally I would probably use the Microsoft ...


1

I don't understand why you're asking this question. If you're buying in a service, then backups should be part of the SLA and not your responsibility. If it's not part of the service, then why are you using SaaS? On the other hand, if you need to be backing up something, why are you backing up every hour? Technically, if your application is running on a ...


1

One of my favorite approaches to problems like these in the context of data warehousing usually takes the form of an agile design practice, where the granularity of a system does not need to always be "rolled up" from the lowest level right away, but can be, as stated in the title of the topic "drilled down" into, as the finer granularity details become ...


1

If you are looking for speed of development, the best database back-end is the one that your team has the most experience with that fits your needs. I have experience with relational databases, so I would likely start with a relational database like MySQL. If I were more familiar with key/value stores I might say something like Riak. I think your best bet ...


1

Yes, it is still recommended not to shrink. If your data file goes up to 20 GB every quarter, then think about this: after you've shrunk it to 5 GB, you've freed up an extra 15 GB on the drive. What are you going to use that space for? Are you going to lease it out to someone temporarily, then kick them off the drive when your database starts to grow again? ...


1

I am not sure that I would consider this to be an issue of inheritance, and from the description, I would say that the Address table would depend on the other two tables instead of those two tables depending on the Address table. But that minutia aside, I would recommend: If you are only storing U.S. or maybe U.S. and Canada addresses, then you can do a ...


1

Both are OK designs, so now the problem is deciding between the two. Here are some things that I think you should consider as you decide which one is best. How similar are the non-essential columns in the Course Subscription and Lesson Subscription tables? If they are very similar then records which contain only a course subscription in the Subscriptions ...


1

Think about how what kind of queries and reports you want to run against your data. Lets say for example you want to know how many students were absent in the month of 2013-10. Here is how that would look with each table: SELECT COUNT(*) FROM TABLEA WHERE DATE BETWEEN TO_DATE('2013-10','YYYY-MM') AND TO_DATE('2013-11')-1/24/60/60 AND STATUS='X'; SELECT ...


1

I would suggest something different than you have here- a separate table to record the student_class relation: | student_id | class | date | ----------------------------------- | 2 | 7 | 2013-10-24 | This would have one record for a student where a class was attended. For each class and date for which there is no record, it can be ...


1

About _id generation, as long as you don't specify _id explicitly, Mongo would handle the id for you. It generates different nonce for different collection. So you should not need to worry about duplicated _id across different collection. Reference here. I agree with other answer, use same collection and put an extra field to differentiate regular user and ...


1

You should not have two collections, that will give you headache. Have a user collection which has admin and regular users. You can then query users as a whole or look for a given type only. So if you are looking for user id x you don't have two search two collections. As for the question on duplicate ids with 2 collections, it simply depends how the ids ...


1

No, there is no requirement for tables to be related to one-another. The fact that you do have two tables separate from the other thirteen would be a code smell and you should be sure that you have not forced two different business objectives into a single database. If the two really do support genuine use cases for the others then there's no problem. A ...


1

When every document is about shoes, then the term "shoe" will likely do little for the relevancy score, which may be enough of a filter in many cases. Still, as you point out, if there are no sport shoes and a document contains multiple occurrences of "shoes", that document may be considered relevant enough to be included in the result and without ...


1

Having had a look at your rethink with just three tables (www.graphicsdesigned.co.uk/MuseumSchema4.gif) it still needs more tweaking. What if a museum is linked to more than one category? The way you have it set up at the moment you'll be adding another row to the museums table for each category that the museum is in. What you need is a "link table" which ...


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Teaching yourself database design is indeed very tricky. You might benefit from finding a good tutorial that would help you master the basics. If you want suggestions concerning a good learning vehicle, ask. Here is a very oversimplified summary of some of the basics. Before you can design a database, you have to analyze the subject matter in some ...


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There are several methods you can use such as mysqldump folder copy enterprise backup for mysqldump use following command: mysqldump -uuser -ppassword --database your_db_name --routines --triggers --events --lock-all-tables >outputfile.sql and use following command at destination: mysql -uroot -ppassword<outputfile.sql. You can also use ...



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