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Storage and computation is getting cheaper AND easily accessible on demand in the cloud. We now collect and store some really large data sets Eg: user activity logs, genome sequencing, sensory data etc. Hadoop and the ecosystem of projects built around it present simple and easy to use tools for storing and analyzing such large data collections on commodity hardware.
Topics Covered
* The Hadoop architecture.
* Thinking in MapReduce.
* Run some sample MapReduce Jobs (using Hadoop Streaming).
* Introduce PigLatin, a easy to use data processing language.
Speaker Profile: Mahesh Reddy is an Entrepreneur, chasing dreams. Works on large scale crawl and extraction of structured data from the web. He is a graduate frm IIT Kanpur(2000-05) and previously worked at Yahoo! Labs as Research Engineer/Tech Lead on Search and Advertising products.
Since its first public release over two decades ago, the Java platform has become ubiquitous in virtually all areas of computing; from embedded systems to enterprise applications. As the demands of modern software development have evolved, so too have programming languages. There are many languages on the Java platform designed to be a “better Java”; though none are as widespread as Java itself. Despite the somewhat conservative nature of Java as a language, there have been a number of notable additions designed to address the challenges developers face without breaking compatibility. This presentation aims to provide an overview of the newer language features and APIs in recent releases of Java in the hope of increasing developer productivity.
Streaming machine learning is being integrated in Spark 2.1+, but you don’t need to wait. Holden Karau and Seth Hendrickson demonstrate how to do streaming machine learning using Spark’s new Structured Streaming and walk you through creating your own streaming model. By the end of this session, you’ll have a better understanding of Spark’s Structured Streaming API as well as how machine learning works in Spark.
I am Samantha K. I am a Database Homework Expert at databasehomeworkhelp.com. I hold a PhD. in Programming, from McGill University, Canada. I have been helping students with their homework for the past 9 years. I solve homework related to Database.
Visit databasehomeworkhelp.com or email info@databasehomeworkhelp.com. You can also call on +1 678 648 4277 for any assistance with Database Homework.
I am Bryson J. I am a Database Homework Expert at databasehomeworkhelp.com. I hold a PhD. in Programming, from Texas University, USA. I have been helping students with their homework for the past 7 years. I solve homework related to Database.
Visit databasehomeworkhelp.com or email info@databasehomeworkhelp.com. You can also call on +1 678 648 4277 for any assistance with Database Homework.
Storage and computation is getting cheaper AND easily accessible on demand in the cloud. We now collect and store some really large data sets Eg: user activity logs, genome sequencing, sensory data etc. Hadoop and the ecosystem of projects built around it present simple and easy to use tools for storing and analyzing such large data collections on commodity hardware.
Topics Covered
* The Hadoop architecture.
* Thinking in MapReduce.
* Run some sample MapReduce Jobs (using Hadoop Streaming).
* Introduce PigLatin, a easy to use data processing language.
Speaker Profile: Mahesh Reddy is an Entrepreneur, chasing dreams. Works on large scale crawl and extraction of structured data from the web. He is a graduate frm IIT Kanpur(2000-05) and previously worked at Yahoo! Labs as Research Engineer/Tech Lead on Search and Advertising products.
Since its first public release over two decades ago, the Java platform has become ubiquitous in virtually all areas of computing; from embedded systems to enterprise applications. As the demands of modern software development have evolved, so too have programming languages. There are many languages on the Java platform designed to be a “better Java”; though none are as widespread as Java itself. Despite the somewhat conservative nature of Java as a language, there have been a number of notable additions designed to address the challenges developers face without breaking compatibility. This presentation aims to provide an overview of the newer language features and APIs in recent releases of Java in the hope of increasing developer productivity.
Streaming machine learning is being integrated in Spark 2.1+, but you don’t need to wait. Holden Karau and Seth Hendrickson demonstrate how to do streaming machine learning using Spark’s new Structured Streaming and walk you through creating your own streaming model. By the end of this session, you’ll have a better understanding of Spark’s Structured Streaming API as well as how machine learning works in Spark.
Emerging technologies /frameworks in Big DataRahul Jain
A short overview presentation on Emerging technologies /frameworks in Big Data covering Apache Parquet, Apache Flink, Apache Drill with basic concepts of Columnar Storage and Dremel.
The current trends to work in Agile and DevOps are challenging for database developers. Source control is a standard for non-database code but it’s a challenge for databases. This talk has an ambition to change that situation and help developers and DBA take over control of source code and data.
The big language features for Java SE 8 are lambda expressions (a.k.a. closures) and default methods (a.k.a. virtual extension methods). Adding closures to the Java language opens up a host of new expressive opportunities for applications and libraries, but how are they implemented? You might assume that lambda expressions are simply a compact syntax for inner classes, but, in fact, the implementation of lambda expressions is substantially different and builds on the invokedynamic feature added in Java SE 7.
Understanding SQL Trace, TKPROF and Execution Plan for beginnersCarlos Sierra
The three fundamental steps of SQL Tuning are: 1) Diagnostics Collection; 2) Root Cause Analysis (RCA); and 3) Remediation. This introductory session on SQL Tuning is for novice DBAs and Developers that are required to investigate a piece of an application performing poorly.
On this session participants will learn about producing a SQL Trace then a summary TKPROF report. A sample TKPROF is navigated with the audience, where the trivial and the no so trivial is exposed and explain. Execution Plans are also navigated and explained, so participants can later untangle complex Execution Plans and start diagnosing SQL performing badly.
This session encourages participants to ask all kind of questions that could be potential road-blocks for deeper understanding of how to address a SQL performing poorly.
Leveraging Hadoop in your PostgreSQL EnvironmentJim Mlodgenski
This talk will begin with a discussion of the strengths of PostgreSQL and Hadoop. We will then lead into a high level overview of Hadoop and its community of projects like Hive, Flume and Sqoop. Finally, we will dig down into various use cases detailing how you can leverage Hadoop technologies for your PostgreSQL databases today. The use cases will range from using HDFS for simple database backups to using PostgreSQL and Foreign Data Wrappers to do low latency analytics on your Big Data.
Presentations from the Cloudera Impala meetup on Aug 20 2013Cloudera, Inc.
Presentations from the Cloudera Impala meetup on Aug 20 2013:
- Nong Li on Parquet+Impala and UDF support
- Henry Robinson on performance tuning for Impala
Lessons learned from years of maintaining/extending/improving an in house CMS. Hopefully these will present things to avoid and things to try that will save others some pain.
Covered:
1. Databases and Schemas
2. Tablespaces
3. Data Type
4. Exploring Databases
5. Locating the database server's message log
6. Locating the database's system identifier
7. Listing databases on this database server
8. How much disk space does a table use?
9. Which are my biggest tables?
10. How many rows are there in a table?
11. Quickly estimating the number of rows in a table
12. Understanding object dependencies
Supporting Over a Thousand Custom Hive User Defined FunctionsDatabricks
Over the years, Facebook has used Hive as the primary query engine to be used by our data engineers. Since Hive uses SQL-like query language called HQL, the list of built-in User Defined Functions (UDFs) did not always satisfy our customer requirements and as a result, an extensive list of custom UDFs was developed over time. As we started migrating pipelines from Hive to Spark SQL, a number of custom UDFs appeared incompatible with Spark, and many others showed bad performance. In this talk will first take a deep dive into how Hive UDFs work with Spark. We will then share what challenges we overcame on the way to support 99.99% of the custom UDFs in Spark.
Speakers: Sergey Makagonov, Xin Yao
Welcome to the wonderful world of Java Streams ported for the CFML world!The beauty of streams is that the elements in a stream are processed and passed across the processing pipeline. Unlike traditional CFML functions like map(), reduce() and filter() which create completely new collections until all items in the pipeline are processed. With streams, the elements are streamed across the pipeline to increase efficiency and performance.
ITB2019 CBStreams : Accelerate your Functional Programming with the power of ...Ortus Solutions, Corp
This session will introduce the cbStreams module. It will discuss what Java streams are, each of the available methods and options, and how to implement cbStreams into their applications. With real-world examples of stream implementation, this session will also show how using streams can enhance the performance of your application and reduce latency. Target Audience: Anyone wishing to learn about Java streams.
Learn the best way to overcome the challenges of your database homework! Our knowledgeable Database Homework Helpers have the skills necessary to handle challenging queries, improve SQL, and interpret ER diagrams. We make sure that your assignments stand out by providing in-depth knowledge and prompt assistance. Obtain success right away with database homework help!
Welcome to Database Homework Help, your one-stop database homework solution! We're here to help you understand database concepts. Our qualified experts are available 24/7 to answer database questions. Our professionals can help you with SQL queries, data normalization, and data modeling. We even specialize in advanced topics like JPA (Java Persistence API) and have attached a sample JPA question for your reference.
Our prompt and personalized assistance can help you overcome database homework challenges and master the subject. Our solutions are clear, concise, and plagiarism-free.
Visit our website, www.databasehomeworkhelp.com.
To get started, email us at info@databasehomeworkhelp.com or call us at +1 (336) 559-3795. Our dedicated team will help you succeed in your database homework.
Emerging technologies /frameworks in Big DataRahul Jain
A short overview presentation on Emerging technologies /frameworks in Big Data covering Apache Parquet, Apache Flink, Apache Drill with basic concepts of Columnar Storage and Dremel.
The current trends to work in Agile and DevOps are challenging for database developers. Source control is a standard for non-database code but it’s a challenge for databases. This talk has an ambition to change that situation and help developers and DBA take over control of source code and data.
The big language features for Java SE 8 are lambda expressions (a.k.a. closures) and default methods (a.k.a. virtual extension methods). Adding closures to the Java language opens up a host of new expressive opportunities for applications and libraries, but how are they implemented? You might assume that lambda expressions are simply a compact syntax for inner classes, but, in fact, the implementation of lambda expressions is substantially different and builds on the invokedynamic feature added in Java SE 7.
Understanding SQL Trace, TKPROF and Execution Plan for beginnersCarlos Sierra
The three fundamental steps of SQL Tuning are: 1) Diagnostics Collection; 2) Root Cause Analysis (RCA); and 3) Remediation. This introductory session on SQL Tuning is for novice DBAs and Developers that are required to investigate a piece of an application performing poorly.
On this session participants will learn about producing a SQL Trace then a summary TKPROF report. A sample TKPROF is navigated with the audience, where the trivial and the no so trivial is exposed and explain. Execution Plans are also navigated and explained, so participants can later untangle complex Execution Plans and start diagnosing SQL performing badly.
This session encourages participants to ask all kind of questions that could be potential road-blocks for deeper understanding of how to address a SQL performing poorly.
Leveraging Hadoop in your PostgreSQL EnvironmentJim Mlodgenski
This talk will begin with a discussion of the strengths of PostgreSQL and Hadoop. We will then lead into a high level overview of Hadoop and its community of projects like Hive, Flume and Sqoop. Finally, we will dig down into various use cases detailing how you can leverage Hadoop technologies for your PostgreSQL databases today. The use cases will range from using HDFS for simple database backups to using PostgreSQL and Foreign Data Wrappers to do low latency analytics on your Big Data.
Presentations from the Cloudera Impala meetup on Aug 20 2013Cloudera, Inc.
Presentations from the Cloudera Impala meetup on Aug 20 2013:
- Nong Li on Parquet+Impala and UDF support
- Henry Robinson on performance tuning for Impala
Lessons learned from years of maintaining/extending/improving an in house CMS. Hopefully these will present things to avoid and things to try that will save others some pain.
Covered:
1. Databases and Schemas
2. Tablespaces
3. Data Type
4. Exploring Databases
5. Locating the database server's message log
6. Locating the database's system identifier
7. Listing databases on this database server
8. How much disk space does a table use?
9. Which are my biggest tables?
10. How many rows are there in a table?
11. Quickly estimating the number of rows in a table
12. Understanding object dependencies
Supporting Over a Thousand Custom Hive User Defined FunctionsDatabricks
Over the years, Facebook has used Hive as the primary query engine to be used by our data engineers. Since Hive uses SQL-like query language called HQL, the list of built-in User Defined Functions (UDFs) did not always satisfy our customer requirements and as a result, an extensive list of custom UDFs was developed over time. As we started migrating pipelines from Hive to Spark SQL, a number of custom UDFs appeared incompatible with Spark, and many others showed bad performance. In this talk will first take a deep dive into how Hive UDFs work with Spark. We will then share what challenges we overcame on the way to support 99.99% of the custom UDFs in Spark.
Speakers: Sergey Makagonov, Xin Yao
Welcome to the wonderful world of Java Streams ported for the CFML world!The beauty of streams is that the elements in a stream are processed and passed across the processing pipeline. Unlike traditional CFML functions like map(), reduce() and filter() which create completely new collections until all items in the pipeline are processed. With streams, the elements are streamed across the pipeline to increase efficiency and performance.
ITB2019 CBStreams : Accelerate your Functional Programming with the power of ...Ortus Solutions, Corp
This session will introduce the cbStreams module. It will discuss what Java streams are, each of the available methods and options, and how to implement cbStreams into their applications. With real-world examples of stream implementation, this session will also show how using streams can enhance the performance of your application and reduce latency. Target Audience: Anyone wishing to learn about Java streams.
Learn the best way to overcome the challenges of your database homework! Our knowledgeable Database Homework Helpers have the skills necessary to handle challenging queries, improve SQL, and interpret ER diagrams. We make sure that your assignments stand out by providing in-depth knowledge and prompt assistance. Obtain success right away with database homework help!
Welcome to Database Homework Help, your one-stop database homework solution! We're here to help you understand database concepts. Our qualified experts are available 24/7 to answer database questions. Our professionals can help you with SQL queries, data normalization, and data modeling. We even specialize in advanced topics like JPA (Java Persistence API) and have attached a sample JPA question for your reference.
Our prompt and personalized assistance can help you overcome database homework challenges and master the subject. Our solutions are clear, concise, and plagiarism-free.
Visit our website, www.databasehomeworkhelp.com.
To get started, email us at info@databasehomeworkhelp.com or call us at +1 (336) 559-3795. Our dedicated team will help you succeed in your database homework.
I am David Smith. Currently associated with databasehomeworkhelp.com as a Database Homework Help tutor. I hold a Ph.D in Database management from Sydney University.See my sample on Introduction to Database Security before hiring. For hiring me, Visit www.databasehomeworkhelp.com or email info@databasehomeworkhelp.com. You can also call on +1 (315) 557-6473
My name is Alicia Linton. I have been associated with databasehomeworkhelp.com as a Database Homework Help expert for the past 7 years and have been helping students with their Database Homework. I have a Ph.D in Database Management from McGill University.
My name is Aaron Pollard. I am associated with databasehomeworkhelp.com for the past 8 years and have been helping students with their Database Homework. I have a Master's in Database Management from the University of British Colombia.
I am Amy Potter. Currently associated with databasehomeworkhelp.com as a Database Homework Help tutor. After completing my Ph.D. at New York University University, I was in search of an opportunity that would expand my area of knowledge hence I decided to help students with their assignments. I have completed several database homework to help students overcome difficulties they often face.
I am Henry Wilkins. Currently associated with databasehomeworkhelp.com as a Database tutor. After completing my Ph.D. at Kingston University, I was in search of an opportunity that would expand my area of knowledge hence I decided to help students with their assignments. I have completed several database homework to date to help students overcome difficulties they often face.
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I am Susan C. Currently associated with databasehomeworkhelp.com as a Database System Assignment Expert. After completing my Master’s Degree in Programming, from Leeds, UK, I was in search of an opportunity that expands my area of knowledge hence I decided to help students with their assignments. I have written various database assignments till date to help students overcome numerous difficulties they face in Database System Assignments.
databasehomeworkhelp.com_ Database System Assignment Help (1).pptxDatabase Homework Help
I am Bryson J. I love exploring new topics. Academic writing seemed an interesting option for me. After working for many years with databasehomeworkhelp.com, I have assisted many students with their assignments. I can proudly say, each student I have served is happy with the quality of the solution that I have provided. I have acquired my PhD. in Programming, from Texas University, USA.
I am Kefa J. I am a Database Homework Expert at databasehomeworkhelp.com. I hold a Ph.D. in Programming, Princeton University, USA. I have been helping students with their homework for the past 7 years. I solve homework related to database.
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I am Elena Y. I am an Instant DBMS Assignment Expert at databasehomeworkhelp.com. I hold a Master’s Degree in Programming, from Leeds, UK. I have been helping students with their homework for the past 9 years. I solve assignments related to Instant DBMS.
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I am Susan C. I am an Instant DBMS Homework Expert at databasehomeworkhelp.com. I hold a Master’s Degree in Programming, from Leeds, UK. I have been helping students with their homework for the past 9 years. I solve homework related to Instant DBMS.
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I am Kefa J. I am a Database Management Homework Expert at databasehomeworkhelp.com. I hold a Ph.D. in Programming, Princeton University, USA. I have been helping students with their homework for the past 12 years. I solve homework related to Database Management.
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Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
1. For Any Help Regarding Database Homework Help
Visit:- https://www.databasehomeworkhelp.com/
Email:- info@databasehomeorkhelp.com
Call/ Text/ WhatsApp: +1(315)557-6473
2. What is SimpleDB?
•
•
A basic database system
What is has
– Heapfiles
– Basic Operators (Scan, Filter, JOIN, Aggregate)
– Buffer Pool
– Transactions
– SQL Frontend
Things it doesn't have
– Query optimizer
– Fancy relational operators (UNION, etc)
– Recovery
– Indices
•
Database Systems
4. Catalog
• Catalog stores a list of available tables, TupleDesc
– void addTable(DbFile d, TupleDesc d)
– DbFile getTable(int tableid)
– TupleDesc getTupleDesc(int tableid)
• Not persisted to disk
DbIterator.java
• Iterator class implemented by all operators
– open()
– close()
– getTupleDesc()
– hasNext()
– next()
– rewind()
• Iterator model: chain iterators together
5. // construct a 3column table schema
Type types[] = new Type[]{ Type.INT_TYPE, Type.INT_TYPE, Type.INT_TYPE };
String names[] = new String[]{ "field0", "field1", "field2" };
TupleDesc descriptor = new TupleDesc(types, names);
// create the table, associate it with some_data_file.dat
// and tell the catalog about the schema of this table.
HeapFile table1 = new HeapFile(new File("some_data_file.dat"), descriptor);
Database.getCatalog().addTable(table1);
// construct the query: we use a simple SeqScan, which spoonfeeds
// tuples via its iterator.
TransactionId tid = new TransactionId();
SeqScan f = new SeqScan(tid, table1.id());
// and run it
f.open();
while (f.hasNext()) {
Tuple tup = f.next();
System.out.println(tup);
}
f.close();
Database.getBufferPool().transactionComplete();
6. HeapFile.java
• An array of HeapPages on disk
• Javadoc is your friend!
• Implement everything except addTuple and removeTuple
HeapPage.java
• Format
– Header is a bitmap
– Page contents are an array of fixedlength Tuples
• Full page size = BufferPool.PAGE_SIZE
• Number of bits in Header = number of Tuples
• Header size + size of tuples =
BufferPool.PAGE_SIZE
7. HeapFileEncoder.java
• Because you haven’t implemented insertTuple, you have no way to create
data files
• HeapFileEncoder converts CSV files to HeapFiles
• Usage:
– java jar dist/simpledb.jar convert csvfile.txt numFields
• Produces a file csvfile.dat, that can be passed to HeapFile
constructor.
BufferPool.java
• Manages cache of pages
– Even from inside DbFile!
You will eventually implement
– locking for transactions
– Flushing of pages for recovery
8. Compiling, Testing, and Running
• Compilation done through the ant tool
– Works a lot like make
Two kinds of tests:
– Unit tests
– System Tests
Demo on debugging using unit tests.
•
•