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Damn Cool Algorithms: Log structured storage. Posted by Nick Johnson | Filed under tech, damn-cool-algorithms Typically, if you're designing a storage system - such as a filesystem, or a database - one of your major concerns is how to store the data on disk.

Damn Cool Algorithms: Log structured storage

You have to take care of allocating space for the objects to be stored, as well as storing the indexing data; you have to worry about what happens when you want to extend an existing object (eg, appending to a file), and you have to take care of fragmentation, which happens when old objects are deleted, and new ones take their place.

All of this adds up to a lot of complexity, and the solutions are often buggy or inefficient. Log structured storage is a technique that takes care of all of these issues. It originated as Log Structured File Systems in the 1980s, but more recently it's seeing increasing use as a way to structure storage in database engines. So far so good. Finding the root of the index warrants a quick aside. Previous PostNext Post <a href=" the discussion thread.


DB-Engines - Knowledge Base of Relational and NoSQL Database Management Systems. Ethereum Project. Solidity — Solidity 0.2.0 documentation. Stumbling Towards Database Change Management. The scale of change in the insurance and financial markets is such that there is little time for the application or database developer to sit back and work out ways of improving the delivery process.

Stumbling Towards Database Change Management

Over time, however, it is possible to improve the process so that individual heroics are required less and less as release and deployment become more managed and predictable. It can be messy and error-prone at times but the long-term benefits make the struggle worthwhile. I worked for 15 years as a DBA and IT Manager in the insurance and financial markets. When I first started out, 'chaotic' would be the best word to describe our approach to the design, development and ongoing maintenance of our business applications and data.

I remember vividly the "Wild West" days when, with only a database backup as a fallback policy, I'd make ad-hoc database changes directly to production with little to no testing. "I've put all the files in this folder" SQLiteStudio. SQLite Home Page. VisTrailsWiki. MySQL. Sample databases. Online GUID Generator. How many GUIDs do you want (1-2000): Uppcase: {} Braces: Hyphens: Results: Use these GUIDs at your own risk!

Online GUID Generator

GUIDs generated by this site do not guarantee uniqueness! What is a GUID? GUID (or UUID) is an acronym for 'Globally Unique Identifier' (or 'Universally Unique Identifier'). How unique is a GUID? 128-bits is big enough and the generation algorithm is unique enough that if 1,000,000,000 GUIDs per second were generated for 1 year the probability of a duplicate would be only 50%. How are GUIDs used? GUIDs are used in enterprise software development in C#, Java, and C++ as database keys, component identifiers, or just about anywhere else a truly unique identifier is required.

More Information About GUIDs Globally Unique Identifier - Wikipedia, the free encyclopedia GUID Structure - Microsoft.comRFC 4122 Contact us: guid dot generator at gmail dot com. PASS - The Professional Association for SQL Server > Home. Master Data Management Solution Offering. From MIKE2.0 Methodology Introduction Note: This page covers Master Data Management (MDM) and Customer Data Integration (CDI) that is considered a subset of MDM. Master Data Management. Connecting to SQL Server using SSMS - Part 1. Data dictionary. Data element name.

A data element name is a name given to a data element in, for example, a data dictionary or metadata registry.

Data element name

In a formal data dictionary, there is often a requirement that no two data elements may have the same name, to allow the data element name to become an identifier, though some data dictionaries may provide ways to qualify the name in some way, for example by the application system or other context in which it occurs. In a database driven data dictionary, the fully qualified data element name may become the primary key, or an alternate key, of a Data Elements table of the data dictionary.

The data element name typically conforms to ISO/IEC 11179 metadata registry naming conventions and has at least three parts: Object, Property and Representation term. Many standards require the use of Upper camel case to differentiate the components of a data element name. Universal Postal Union – Home. Agile Data Home Page. Simple Talk: SQL Server and .Net articles, forums and blogs. Good stuff for serious developers: Programming Tools, Code, C++, Java, HTML5, Cloud, Mobile, Testing.

SQuirreL SQL Client Home Page. Toad - SQL Tuning, Database Development & Administration Software. Oracle Toad simplifies the manual, time-intensive tasks associated with Oracle development, administration, performance management, and querying and reporting.

Toad - SQL Tuning, Database Development & Administration Software

It provides Oracle-specific capabilities that enable you to meet SLAs with ease. Plus, Toad can help you with change, configuration, and release management. SQL Server Ensuring good SQL Server performance is demanding work. While your company’s IT budget may not be expanding, the volume of data you’re expected to manage certainly is. Sybase Our Sybase tools make it incredibly easy to manage databases that support the critical applications on which your organization relies. MySQL. SQLAlchemy - The Database Toolkit for Python. The column-store pioneer. The Big Data Analytics Server. Download LINQPad.

PlanetData. Big Data Tools. A Simple Guide to Five Normal Forms in Relational Database Theory. William Kent, "A Simple Guide to Five Normal Forms in Relational Database Theory", Communications of the ACM 26(2), Feb. 1983, 120-125.

A Simple Guide to Five Normal Forms in Relational Database Theory

Also IBM Technical Report TR03.159, Aug. 1981.