Read Chapter 3.1
... Consider each pair of tuples tr from r and ts from s. If tr and ts have the same value on each of the attributes in R S, add a tuple t to the result, where t has the same value as t on r ...
... Consider each pair of tuples tr from r and ts from s. If tr and ts have the same value on each of the attributes in R S, add a tuple t to the result, where t has the same value as t on r ...
Database Recovery
... After the completion of the static backup, still backup log file, when a disk failure occurred, we can load the backup of the data and use the copy of log to redo the completed transaction We can restore the database to the correct state before failure at a certain time, but we do not need to re ...
... After the completion of the static backup, still backup log file, when a disk failure occurred, we can load the backup of the data and use the copy of log to redo the completed transaction We can restore the database to the correct state before failure at a certain time, but we do not need to re ...
Nested Relational Databases
... Limits of 1NF Relational Databases With any relational database system, conformance to the higher normal forms is completely up to the database designer--the software imposes no constraints that prevent attaining an optimal schema, whether fully conformant or not. But databases that provide for the ...
... Limits of 1NF Relational Databases With any relational database system, conformance to the higher normal forms is completely up to the database designer--the software imposes no constraints that prevent attaining an optimal schema, whether fully conformant or not. But databases that provide for the ...
Chapter 7 (Part 1)
... counterpart in the second table. One-to-one relationships are rarely used because it is often more efficient to simply put all of the information in a single table. It would be possible, although not really desirable, to store all the information in one table in this case. ...
... counterpart in the second table. One-to-one relationships are rarely used because it is often more efficient to simply put all of the information in a single table. It would be possible, although not really desirable, to store all the information in one table in this case. ...
O'Brien - Intro. to Information Systems
... Managing Data Resources Types of Databases Data Warehouses The Database Management Approach Section II Technical Foundations of Database Management Database Structures Database Development ...
... Managing Data Resources Types of Databases Data Warehouses The Database Management Approach Section II Technical Foundations of Database Management Database Structures Database Development ...
Review 2
... • FK must be null or have a value that appears as a PK value 5. semantic integrity • other rules that the application domain requires: • state constraint: gross salary > net income • transition constraint: Widowed can only follow Married; salary of an employee cannot decrease Sept. 2012 ...
... • FK must be null or have a value that appears as a PK value 5. semantic integrity • other rules that the application domain requires: • state constraint: gross salary > net income • transition constraint: Widowed can only follow Married; salary of an employee cannot decrease Sept. 2012 ...
Partial Database Availability
... For More Information ......................................................................................40 ...
... For More Information ......................................................................................40 ...
original - Kansas State University
... create view v as < query expression > where is any legal SQL expression. The
view name is represented by v.
Once a view is defined, the view name can be used to refer to
the virtual relation that the view generates.
View definition is not the same as creating a new relation by ...
... create view v as < query expression > where
DBTaint: Cross-Application Information Flow Tracking via Databases
... Information flow tracking has been very successful in protecting software from malicious input. The program identifies the sources of untrusted input, tracks the flow of such input, and prevents this input from being used in security sensitive contexts, such as the return addresses of function calls ...
... Information flow tracking has been very successful in protecting software from malicious input. The program identifies the sources of untrusted input, tracks the flow of such input, and prevents this input from being used in security sensitive contexts, such as the return addresses of function calls ...
(A) R
... Use the union rule to replace any dependencies in F 1 1 and 1 2 with 1 1 2 Find a functional dependency with an extraneous attribute either in or in If an extraneous attribute is found, delete it from until F does not change Note: Union rule may become applicable after ...
... Use the union rule to replace any dependencies in F 1 1 and 1 2 with 1 1 2 Find a functional dependency with an extraneous attribute either in or in If an extraneous attribute is found, delete it from until F does not change Note: Union rule may become applicable after ...
How to Deal with an Oversize Transaction Log
... When you add, edit or delete a record in a SQL Server database the change is written first to the transaction log. A background process subsequently writes each transaction in the log to the database then marks the transaction in the log to show it has been “written”. If the database is set to use t ...
... When you add, edit or delete a record in a SQL Server database the change is written first to the transaction log. A background process subsequently writes each transaction in the log to the database then marks the transaction in the log to show it has been “written”. If the database is set to use t ...
DBC-e05-Chapter-03-PP
... options for processing a single table • Learn basic SQL SELECT statements for processing multiple tables with subqueries • Learn basic SQL SELECT statements for processing multiple tables with joins • Learn SQL statements to modify and delete data from a database • Learn SQL statements to modify and ...
... options for processing a single table • Learn basic SQL SELECT statements for processing multiple tables with subqueries • Learn basic SQL SELECT statements for processing multiple tables with joins • Learn SQL statements to modify and delete data from a database • Learn SQL statements to modify and ...
Introduction to SQL
... some of their attributes null signifies an unknown value or that a value does not exist. The result of any arithmetic expression involving null is null ...
... some of their attributes null signifies an unknown value or that a value does not exist. The result of any arithmetic expression involving null is null ...
Copyright © 2014 Oracle and/or its affiliates. All rights reserved.
... Cut DBA patching efforts from 3,600 hours down to 540 hours Using EM, Cisco lowered their downtime for maintenance by 50% Reduced human error and incidents during patching and upgrades Systems are now highly scalable and automated Saved over $200K per year in IT operational costs with patching autom ...
... Cut DBA patching efforts from 3,600 hours down to 540 hours Using EM, Cisco lowered their downtime for maintenance by 50% Reduced human error and incidents during patching and upgrades Systems are now highly scalable and automated Saved over $200K per year in IT operational costs with patching autom ...
Best Practices for the SAS® Scoring Accelerator for DB2
... multiple database partitions in order to enable parallel processing of large data volumes. The rows of large database tables are evenly distributed across the database partitions through a hash function. The database partitions can then work in parallel, each processing a subset of a table ("divide ...
... multiple database partitions in order to enable parallel processing of large data volumes. The rows of large database tables are evenly distributed across the database partitions through a hash function. The database partitions can then work in parallel, each processing a subset of a table ("divide ...
The Relational Model
... 1. No two distinct tuples can have same values in all key fields, and 2. This is not true for any subset of the key. Part 2 false? A superkey. If there’s >1 key for a relation (these would be called candidate keys), one of the keys is chosen (by DBA) to be the primary key. ...
... 1. No two distinct tuples can have same values in all key fields, and 2. This is not true for any subset of the key. Part 2 false? A superkey. If there’s >1 key for a relation (these would be called candidate keys), one of the keys is chosen (by DBA) to be the primary key. ...
SAP HANA SPS 09 - What`s New? SAP HANA Multitenant Database
... – Can restart the system database itself and can restart individual tenant databases – Can initiate backups of the system database itself and of individual tenant databases. – Recoveries are always initiated by the system database – Tenant databases - always created/dropped by the system database – ...
... – Can restart the system database itself and can restart individual tenant databases – Can initiate backups of the system database itself and of individual tenant databases. – Recoveries are always initiated by the system database – Tenant databases - always created/dropped by the system database – ...
Hashing
... the form (a1 A a2), (b1 B b2) as well as (a1 A a2 b1 B b2), with reasonable efficiency. ...
... the form (a1 A a2), (b1 B b2) as well as (a1 A a2 b1 B b2), with reasonable efficiency. ...
System Administration Certification exam 918 for IBM Informix
... A sensor is a specialized TASK for collecting and saving data. A sensor can be created the same way as a task by inserting a row in the ph_task table, with some additional information. To set up a new sensor, you need to plan first. You need to have: • A description of the sensor • The result table ...
... A sensor is a specialized TASK for collecting and saving data. A sensor can be created the same way as a task by inserting a row in the ph_task table, with some additional information. To set up a new sensor, you need to plan first. You need to have: • A description of the sensor • The result table ...
