Solr and Lucene work with your data as “documents”, which are simply collections of fields. These fields are name-value pairs containing text, numbers, or lists of text and numbers. Adding a document to the index sends the data through a series of "analyzers" -- which can chop off stems (stemming), substitute synonyms, etc -- resulting in a set of "terms". Lucene can then store the location of the terms in the document using an inverted index, which lets it keep track of which terms occur in which documents, where and how many times. You can also apply analyzers when servicing a query.

Storing documents is very different from keeping data in a relational database management system (RDBMS). While RDBMS’s are very good at general tasks, they're not very suited for search. The data inside an RDBMS is normalized which means that data is distributed in a way that keeps repetition to a minimum. Solr/Lucene, on the other hand, is document-oriented and stores data in a de-normalized form. This helps it keep data that will be accessed together and in the form we'd ultimately like to see it, making searches faster.

So, instead of calculating them on the fly, we do all that work ahead of time and push it into Solr. And this data will often be redundant by design. One might think this is inefficient in terms of storage space, but Solr/Lucene is tuned to be very smart about the way it stores data. Because of the inverted index, most terms will only be stored once, with pointers to their associated documents. And, at the document level, you have the option of storing and indexing independently.

Grails is based on the idea that web development should be fast and flexible: that as little as possible should stand between a developer and the application. It is an open-source framework that can allow a developer to get a web application going in minutes rather than being up to their neck in database scripts, XML files and bean definitions. Code is usually written in Groovy, which makes it easy to keep things simple.

Inspired by Ruby on Rails, Grails allows a developer to create objects in the database, generate tests and automatically wire all the elements together on the fly. Though Grails is designed to keep things simple, it is built on proven technologies like JVMs, Spring and Hibernate, so the full power of all those technologies is available should the project require it. Also, a huge ecosystem of easy-to-install plugins exists with a very large community of developers supporting them. In fact, Grails itself is supported by SpringSource (the people behind Spring). Grails-based applications can also be deployed as a WAR to any standard servlet container. In short, Grails’ strength is in its simplicity and flexibility: one needn’t open a toolbox unless they need a specific tool.

I am the very model of a modern Major-General. I've information vegetable, animal, and mineral. I know the kings of England, and I quote the fights historical from Marathon to Waterloo, in order categorical.

I'm very well acquainted, too, with matters mathematical. I understand equations, both the simple and quadratical. About binomial theorem I'm teeming with a lot o' news, with many cheerful facts about the square of the hypotenuse. I'm very good at integral and differential calculus. I know the scientific names of beings animalculous.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. I know our mythic history, King Arthur's and Sir Caradoc's. I answer hard acrostics, I've a pretty taste for paradox. I quote in elegiacs all the crimes of Heliogabalus. In conics I can floor peculiarities parabolous. I can tell undoubted Raphaels from Gerard Dows and Zoffanies. I know the croaking chorus from The Frogs of Aristophanes!

Then I can hum a fugue of which I've heard the music's din afore and whistle all the airs from that infernal nonsense Pinafore. Then I can write a washing bill in Babylonic cuneiform, and tell you ev'ry detail of Caractacus's uniform.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. In fact, when I know what is meant by "mamelon" and "ravelin". When I can tell at sight a Mauser rifle from a Javelin. When such affairs as sorties and surprises I'm more wary and when I know precisely what is meant by "commissariat". When I have learnt what progress has been made in modern gunnery, when I know more of tactics than a novice in a nunnery— In short, when I've a smattering of elemental strategy— You'll say a better Major-General has never sat a gee. For my military knowledge, though I'm plucky and adventury, has only been brought down to the beginning of the century; But still, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General.

I am the very model of a modern Major-General. I've information vegetable, animal, and mineral. I know the kings of England, and I quote the fights historical from Marathon to Waterloo, in order categorical.

I'm very well acquainted, too, with matters mathematical. I understand equations, both the simple and quadratical. About binomial theorem I'm teeming with a lot o' news, with many cheerful facts about the square of the hypotenuse. I'm very good at integral and differential calculus. I know the scientific names of beings animalculous.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. I know our mythic history, King Arthur's and Sir Caradoc's. I answer hard acrostics, I've a pretty taste for paradox. I quote in elegiacs all the crimes of Heliogabalus. In conics I can floor peculiarities parabolous. I can tell undoubted Raphaels from Gerard Dows and Zoffanies. I know the croaking chorus from The Frogs of Aristophanes!

Then I can hum a fugue of which I've heard the music's din afore and whistle all the airs from that infernal nonsense Pinafore. Then I can write a washing bill in Babylonic cuneiform, and tell you ev'ry detail of Caractacus's uniform.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. In fact, when I know what is meant by "mamelon" and "ravelin". When I can tell at sight a Mauser rifle from a Javelin. When such affairs as sorties and surprises I'm more wary and when I know precisely what is meant by "commissariat". When I have learnt what progress has been made in modern gunnery, when I know more of tactics than a novice in a nunnery— In short, when I've a smattering of elemental strategy— You'll say a better Major-General has never sat a gee. For my military knowledge, though I'm plucky and adventury, has only been brought down to the beginning of the century; But still, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General.

I am the very model of a modern Major-General. I've information vegetable, animal, and mineral. I know the kings of England, and I quote the fights historical from Marathon to Waterloo, in order categorical.

I'm very well acquainted, too, with matters mathematical. I understand equations, both the simple and quadratical. About binomial theorem I'm teeming with a lot o' news, with many cheerful facts about the square of the hypotenuse. I'm very good at integral and differential calculus. I know the scientific names of beings animalculous.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. I know our mythic history, King Arthur's and Sir Caradoc's. I answer hard acrostics, I've a pretty taste for paradox. I quote in elegiacs all the crimes of Heliogabalus. In conics I can floor peculiarities parabolous. I can tell undoubted Raphaels from Gerard Dows and Zoffanies. I know the croaking chorus from The Frogs of Aristophanes!

Then I can hum a fugue of which I've heard the music's din afore and whistle all the airs from that infernal nonsense Pinafore. Then I can write a washing bill in Babylonic cuneiform, and tell you ev'ry detail of Caractacus's uniform.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. In fact, when I know what is meant by "mamelon" and "ravelin". When I can tell at sight a Mauser rifle from a Javelin. When such affairs as sorties and surprises I'm more wary and when I know precisely what is meant by "commissariat". When I have learnt what progress has been made in modern gunnery, when I know more of tactics than a novice in a nunnery— In short, when I've a smattering of elemental strategy— You'll say a better Major-General has never sat a gee. For my military knowledge, though I'm plucky and adventury, has only been brought down to the beginning of the century; But still, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General.

I am the very model of a modern Major-General. I've information vegetable, animal, and mineral. I know the kings of England, and I quote the fights historical from Marathon to Waterloo, in order categorical.

I'm very well acquainted, too, with matters mathematical. I understand equations, both the simple and quadratical. About binomial theorem I'm teeming with a lot o' news, with many cheerful facts about the square of the hypotenuse. I'm very good at integral and differential calculus. I know the scientific names of beings animalculous.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. I know our mythic history, King Arthur's and Sir Caradoc's. I answer hard acrostics, I've a pretty taste for paradox. I quote in elegiacs all the crimes of Heliogabalus. In conics I can floor peculiarities parabolous. I can tell undoubted Raphaels from Gerard Dows and Zoffanies. I know the croaking chorus from The Frogs of Aristophanes!

Then I can hum a fugue of which I've heard the music's din afore and whistle all the airs from that infernal nonsense Pinafore. Then I can write a washing bill in Babylonic cuneiform, and tell you ev'ry detail of Caractacus's uniform.

In short, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General. In fact, when I know what is meant by "mamelon" and "ravelin". When I can tell at sight a Mauser rifle from a Javelin. When such affairs as sorties and surprises I'm more wary and when I know precisely what is meant by "commissariat". When I have learnt what progress has been made in modern gunnery, when I know more of tactics than a novice in a nunnery— In short, when I've a smattering of elemental strategy— You'll say a better Major-General has never sat a gee. For my military knowledge, though I'm plucky and adventury, has only been brought down to the beginning of the century; But still, in matters vegetable, animal, and mineral, I am the very model of a modern Major-General.