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1500 questions
31
votes
4 answers

Best way to create a materialized view in MySQL

I am using MySQL 5.6. I am not being able to a create materialized view like I can in Oracle. I have seen one or two solutions like Flexview. Can anybody tell me best way to create a materialized view in MySQL (auto refresh like in Oracle ) with the…
Bhupendra Pandey
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31
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3 answers

What is a deterministic method for evaluating a sensible buffer pool size?

I'm trying to come up with a sane way to understand if the max server memory (mb) setting is appropriate (either should be lower, or higher, or stay the way it is). I am aware that max server memory (mb) should always be low enough to leave room…
Hannah Vernon
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31
votes
3 answers

Mnesia: advantages and differences

What are the advantages of Mnesia over major SQL database implementations and how it differs to them? Can I use the database to hold really huge amounts of data without noticeable performance degradation ?
Yasir Arsanukayev
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31
votes
5 answers

CREATE DATABASE permission denied in database 'master'. unable to get the permission

I am making a database in sql server and it shows an error that "CREATE DATABASE permission denied in database 'master'" I am using the administrator log in itself. What i need to do? Please suggest a fix!
Shubhankar
31
votes
2 answers

How to use COALESCE with multiple rows and without preceding comma?

I'm trying to achieve the following: California | Los Angeles, San Francisco, Sacramento Florida | Jacksonville, Miami Unfortunately, I'm getting ",Los Angeles, San Francisco, Sacramento, Jacksonville, Miami" I can achieve my desired results…
user2732180
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31
votes
1 answer

Why is the speed of executing statements dependent on the network connection?

It looks like the speed of executing T-SQL is dependent on the latency of the network connection against the server. I assumed that if SQL Server has nothing to report back to the client about, it will just execute away until it is done but testing…
Mikael Eriksson
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31
votes
5 answers

Is there a "best-practices" type process for developers to follow for database changes?

What is a good way to migrate DB changes from Development to QA to Production environments? Currently we: Script the change in a SQL file and attach that to a TFS work item. The work is peer-reviewed When the work is ready for testing then the SQL…
Beth Lang
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31
votes
3 answers

Foreign key constraint on array member?

Suppose I have a table containing job roles: CREATE TABLE roles ( "role" character varying(80) NOT NULL, CONSTRAINT "role" PRIMARY KEY (role) ); Suppose I further have a table, users, and each row (a specific user) can have an arbitrary number…
user2965107
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31
votes
4 answers

What steps are necessary to safely restart a machine hosting Microsoft SQL Server?

Are there any special steps necessary to prevent data corruption when restarting a server hosting an MS SQL Server instance? For example, I recently encountered the recommendation of stopping the SQL service manually. My understanding is that this…
Jon of All Trades
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31
votes
1 answer

Designing a platform: one database or multiple databases?

We are building a web platform that incorporates multiple services, each with its own underlying data. These services are being built independently following the principles of Service-Oriented Architecture, but they transact against potentially…
Nick Chammas
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31
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4 answers

Adding columns to production tables

What's the best way to add columns to large production tables on SQL Server 2008 R2? According to Microsoft's books online: The changes specified in ALTER TABLE are implemented immediately. If the changes require modifications of the rows in the…
sh-beta
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31
votes
2 answers

MySQL and window functions

It seems that MySQL does not support window functions. E.g. the simple: COUNT(*) OVER() AS cnt does not work. What I am not sure is if this applies to commercial version as well (I assume the community version is limited subset). If not, how does…
Cratylus
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31
votes
2 answers

Using MongoDB and PostgreSQL together

My current project is essentially a run of the mill document management system. That said, there are some wrinkles (surprise, surprise). While some of the wrinkles are fairly specific to the project, I believe there are some general observations…
chucksmash
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31
votes
2 answers

How can I determine the size of a dump file prior to dumping?

How can I determine or estimate the size of the SQL dump file prior to using something like mysqldump?
Micah Bolen
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31
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1 answer

Trigger in combination with transaction

Suppose we have the following situation: We have a table (let's say Table_A), wich has a trigger on INSERT. The trigger job is to update some rows in table_B based on the inserted values in table_A. Now, everything is ok when we simple insert a row…
veljasije
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