No Slide Title
... Essentiality maintains functionality. Codd used ‘Essentiality’ to create relational DBs. • Only one essential data construct, the relation. • Earlier database models had 2 or more data constructs, but only the functionality of relations. greater complexity. (NB Each construct requires its own oper ...
... Essentiality maintains functionality. Codd used ‘Essentiality’ to create relational DBs. • Only one essential data construct, the relation. • Earlier database models had 2 or more data constructs, but only the functionality of relations. greater complexity. (NB Each construct requires its own oper ...
R - METU Computer Engineering
... – Choose the best and “nearly best” plans for each (a plan is considered nearly best if its output has some “interesting” form, e.g., is sorted) – Combine these 1-relation plans into 2-relation expressions. Retain only the best and nearly best 2relation plans – Do same for 3-relation expressions, et ...
... – Choose the best and “nearly best” plans for each (a plan is considered nearly best if its output has some “interesting” form, e.g., is sorted) – Combine these 1-relation plans into 2-relation expressions. Retain only the best and nearly best 2relation plans – Do same for 3-relation expressions, et ...
Object-Relational Mapping with Hibernate and JPA
... The world consists of objects So we use object-oriented languages to write applications We want to store some of the application objects (a.k.a. persistent objects) So we use a Object Database? ...
... The world consists of objects So we use object-oriented languages to write applications We want to store some of the application objects (a.k.a. persistent objects) So we use a Object Database? ...
Interacting with the Oracle Server
... using the SELECT command • Make changes to rows in the database by using DML commands • Control a transaction with the COMMIT, ROLLBACK, or SAVEPOINT command • Determine DML outcome with implicit cursor attributes ...
... using the SELECT command • Make changes to rows in the database by using DML commands • Control a transaction with the COMMIT, ROLLBACK, or SAVEPOINT command • Determine DML outcome with implicit cursor attributes ...
Word Document - Dr. Selim Akyokuş
... Basic concepts of database systems; The relational model: domains and relations, data integrity, relational algebra, relational calculus, SQL; Database design: functional dependencies, normalization, entity/relationship model; File Structures, indexing and hashing; Data protection: recovery, concurr ...
... Basic concepts of database systems; The relational model: domains and relations, data integrity, relational algebra, relational calculus, SQL; Database design: functional dependencies, normalization, entity/relationship model; File Structures, indexing and hashing; Data protection: recovery, concurr ...
No Slide Title
... Equivalence of FD sets: FD sets F and G are equivalent if the imply the same set of FD’s e.g. A B and B C : implies A C equivalence usually expressed in terms of closures ...
... Equivalence of FD sets: FD sets F and G are equivalent if the imply the same set of FD’s e.g. A B and B C : implies A C equivalence usually expressed in terms of closures ...
Chapter 4: SQL
... Ensures that a value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation. Example: If “Biology” is a department name appearing in one of the tuples in the instructor relation, then there exists a tuple in the department relati ...
... Ensures that a value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation. Example: If “Biology” is a department name appearing in one of the tuples in the instructor relation, then there exists a tuple in the department relati ...
COP5725 Advanced Database - Florida State University
... Office Hours : M 5-6:00, Tu 12:30-2:30, W 12:30-2:30 ...
... Office Hours : M 5-6:00, Tu 12:30-2:30, W 12:30-2:30 ...
Conceptual Design Using the ER Model
... Blocked I/O is used because reading a 32-page block is faster than 32 separate 1-page I/Os. For each sorting pass, you still must read and write every page in the file, but instead of doing 10,000 1-page I/Os, instead you do (10,000/32) block I/Os. Assume that in our system, we can read a 32-page bl ...
... Blocked I/O is used because reading a 32-page block is faster than 32 separate 1-page I/Os. For each sorting pass, you still must read and write every page in the file, but instead of doing 10,000 1-page I/Os, instead you do (10,000/32) block I/Os. Assume that in our system, we can read a 32-page bl ...
Databases course of 2017-03-02
... SELECT list of table columns/fields in the result (or * for all) ...
... SELECT list of table columns/fields in the result (or * for all) ...
A Universal Relation Database Interface for Knowledge Based
... In this case there will be three temporary database tables. The last structure of the SQL query corresponds to the resulting table that is output to the user. The query could be written more compactly and efficiently as a single query with a subquery, but this does not generally apply to more comple ...
... In this case there will be three temporary database tables. The last structure of the SQL query corresponds to the resulting table that is output to the user. The query could be written more compactly and efficiently as a single query with a subquery, but this does not generally apply to more comple ...
Selectivity Estimation using Probabilistic Models Lise Getoor Ben Taskar Daphne Koller
... dimensional case. A newer approach is the use of wavelets to approximate the underlying joint distribution [21, 27, 6]. Much less work has been done on estimating the selectivity of joins. Commercial DBMSs commonly make the uniform join assumption. One approach that has been suggested is based on r ...
... dimensional case. A newer approach is the use of wavelets to approximate the underlying joint distribution [21, 27, 6]. Much less work has been done on estimating the selectivity of joins. Commercial DBMSs commonly make the uniform join assumption. One approach that has been suggested is based on r ...
mod-6
... Outer Join An extension of the join operation that avoids loss of information. Computes the join and then adds tuples form one relation that ...
... Outer Join An extension of the join operation that avoids loss of information. Computes the join and then adds tuples form one relation that ...
Chapter 5: Other Relational Languages
... tuples to the user, the selected tuples are removed from the database. Can delete only whole tuples; cannot delete values on only particular attributes A deletion is expressed in relational algebra by: ...
... tuples to the user, the selected tuples are removed from the database. Can delete only whole tuples; cannot delete values on only particular attributes A deletion is expressed in relational algebra by: ...
person-name
... Representing Specialization as Tables Method 1: Form a table for the higher level entity Form a table for each lower level entity set, include primary key of higher level entity set and local attributes table table attributes person name, street, city customer name, credit-rating employee nam ...
... Representing Specialization as Tables Method 1: Form a table for the higher level entity Form a table for each lower level entity set, include primary key of higher level entity set and local attributes table table attributes person name, street, city customer name, credit-rating employee nam ...
A Software Tool to Transform Relational Databases in order to Mine
... Relationship model, the initial design must be refined. Functional dependencies form an important class of integrity constraints. The relation scheme obtained by translating the Entity-Relationship model is a good starting point, but we still need to develop new techniques to detect possible redunda ...
... Relationship model, the initial design must be refined. Functional dependencies form an important class of integrity constraints. The relation scheme obtained by translating the Entity-Relationship model is a good starting point, but we still need to develop new techniques to detect possible redunda ...
ppt
... • Concurrent (interleaved) execution of a set of transactions offers performance benefits, but might not be correct. • Example: Two students execute the course registration transaction at about the same time (cur_reg is the number of current registrants) T1: read(cur_reg : 29) T2: ...
... • Concurrent (interleaved) execution of a set of transactions offers performance benefits, but might not be correct. • Example: Two students execute the course registration transaction at about the same time (cur_reg is the number of current registrants) T1: read(cur_reg : 29) T2: ...
DBXplorer: A system for keyword based search over relational
... column c2, we retain only values in c1 CP-Comp: It is used when pairs of columns share common keywords but are not tied by FK ...
... column c2, we retain only values in c1 CP-Comp: It is used when pairs of columns share common keywords but are not tied by FK ...
A*: Algebra for an Extended Object/Relational Model
... based on relational algebra and a relational calculation language based on the logic of first order. The logical aspect of the relational calculation allows the user to specify a query in a declarative way. In particular, the user does not need to know how data are physically stored in the database ...
... based on relational algebra and a relational calculation language based on the logic of first order. The logical aspect of the relational calculation allows the user to specify a query in a declarative way. In particular, the user does not need to know how data are physically stored in the database ...