Chapter 17: Parallel Databases
... Comparison of Partitioning Techniques (Cont.) Range partitioning: Provides data clustering by partitioning attribute value. Good for sequential access Good for point queries on partitioning attribute: only one disk needs to be accessed. For range queries on partitioning attribute, one to a ...
... Comparison of Partitioning Techniques (Cont.) Range partitioning: Provides data clustering by partitioning attribute value. Good for sequential access Good for point queries on partitioning attribute: only one disk needs to be accessed. For range queries on partitioning attribute, one to a ...
Practical Database Design and Tuning
... Tuning the Database Design (contd.) • Possible changes to the database design →Existing tables may be joined (denormalized) because certain attributes from two or more tables are frequently needed together. →For the given set of tables, there may be alternative design choices, all of which achieve ...
... Tuning the Database Design (contd.) • Possible changes to the database design →Existing tables may be joined (denormalized) because certain attributes from two or more tables are frequently needed together. →For the given set of tables, there may be alternative design choices, all of which achieve ...
A Probe-Based Technique to Optimize Join Queries in Distributed Internet Databases
... In a distributed database system, some queries require the participation of multiple sites, each processing part of the query as well as transferring data back and forth among themselves. Since usually there is more than one plan to execute such a query, it is crucial to obtain the cost of each plan ...
... In a distributed database system, some queries require the participation of multiple sites, each processing part of the query as well as transferring data back and forth among themselves. Since usually there is more than one plan to execute such a query, it is crucial to obtain the cost of each plan ...
On the complexity of nested relational operations
... We do not give the detailed proofs here, they can be found in [Sch88]. Union might be considered a linear operation if we omit duplicate elimination as with projections. Otherwise it requires sorting like difference, intersection and nesting do, hence they are not linear. As input relations for a pr ...
... We do not give the detailed proofs here, they can be found in [Sch88]. Union might be considered a linear operation if we omit duplicate elimination as with projections. Otherwise it requires sorting like difference, intersection and nesting do, hence they are not linear. As input relations for a pr ...
Reverse Query Processing Carsten Binnig, Donald Kossmann and
... • Error is returned if input does not match the selection predicate. • If additional tuple are generated than they must satisfy the negation of the selection predicate. ...
... • Error is returned if input does not match the selection predicate. • If additional tuple are generated than they must satisfy the negation of the selection predicate. ...
Course Design in Database Lecture 1
... Since we allow open more than one database simultaneously, the DB manager should maintain all opened databases in current system. Maintain system tables for each database package the result from the low-level system, and send it to the right session Logger ...
... Since we allow open more than one database simultaneously, the DB manager should maintain all opened databases in current system. Maintain system tables for each database package the result from the low-level system, and send it to the right session Logger ...
Genome Wide Visualization and Integration
... C. J. DATE, An Introduction to Database Systems, Addison-Wesley 8th Edition (2003) ...
... C. J. DATE, An Introduction to Database Systems, Addison-Wesley 8th Edition (2003) ...
Chapter 5 File
... A set S of relation schemas that belong to the same database. S is the name of the whole database schema S = {R1, R2, ..., Rn} R1, R2, …, Rn are the names of the individual relation schemas within the database S ...
... A set S of relation schemas that belong to the same database. S is the name of the whole database schema S = {R1, R2, ..., Rn} R1, R2, …, Rn are the names of the individual relation schemas within the database S ...
Course Outline 2016 INFOSYS 222: DATABASE
... data modelling and structured query language (SQL) Learning Outcomes By the end of this course it is expected that student will be able to: 1. understand the fundamental concepts of relational database; 2. design a relational database; 3. implement a relational database; 4. define and manage data fr ...
... data modelling and structured query language (SQL) Learning Outcomes By the end of this course it is expected that student will be able to: 1. understand the fundamental concepts of relational database; 2. design a relational database; 3. implement a relational database; 4. define and manage data fr ...
Chapter 7: Relational Database Design
... customer, with depositor as the outer relation. Let customer have a primary B+-tree index on the join attribute customer-name, which contains 20 entries in each index node. Since customer has 10,000 tuples, the height of the tree is 4, and one more access is needed to find the actual data ...
... customer, with depositor as the outer relation. Let customer have a primary B+-tree index on the join attribute customer-name, which contains 20 entries in each index node. Since customer has 10,000 tuples, the height of the tree is 4, and one more access is needed to find the actual data ...
FinalExamReview
... 4. What is a B+ tree index? What are the main properties of B+ tree? 5. How to build a B+ tree given a sequence of search keys? 6. What are the benefits of having indexes on attributes of tables? 7. What are the overhead of having an index? 8. How to choose which attribute(s) to build an index? 9. U ...
... 4. What is a B+ tree index? What are the main properties of B+ tree? 5. How to build a B+ tree given a sequence of search keys? 6. What are the benefits of having indexes on attributes of tables? 7. What are the overhead of having an index? 8. How to choose which attribute(s) to build an index? 9. U ...
PPT
... The set of allowed values for each attribute is called the domain of the attribute Attribute values are (normally) required to be atomic; that is, indivisible The special value null is a member of every domain The null value causes complications in the definition of many operations ...
... The set of allowed values for each attribute is called the domain of the attribute Attribute values are (normally) required to be atomic; that is, indivisible The special value null is a member of every domain The null value causes complications in the definition of many operations ...
Database Security
... Importance of Database Security Why securing data stored in databases so important and different? ●Databases store massive amounts of sensitive data ●Data has structure that influences how it is accessed ●Accessed via queries or programs written in languages like SQL (Structured Query Language) ●Tr ...
... Importance of Database Security Why securing data stored in databases so important and different? ●Databases store massive amounts of sensitive data ●Data has structure that influences how it is accessed ●Accessed via queries or programs written in languages like SQL (Structured Query Language) ●Tr ...
ppt
... create table students of Student under people create table teachers of Teacher under people create table teaching-assistants of Teaching Assistant under students, teachers In relational systems, sub and super tables would have to be linked ...
... create table students of Student under people create table teachers of Teacher under people create table teaching-assistants of Teaching Assistant under students, teachers In relational systems, sub and super tables would have to be linked ...
What is a Database System?
... R and P - two relations to be joined J - the attribute on which the (natural) join is performed R[i] and P[j] mean the i-th tuple of R and the j-th tuple of P, respectively R[i].J means the value of the attribute J for the i-th tuple of the relation R R has M and P has N tuples, respective ...
... R and P - two relations to be joined J - the attribute on which the (natural) join is performed R[i] and P[j] mean the i-th tuple of R and the j-th tuple of P, respectively R[i].J means the value of the attribute J for the i-th tuple of the relation R R has M and P has N tuples, respective ...
