CS194Lec03DataModels - b
... – Data is simply copied to the file store, no transformation is needed. – A SerDe (Serializer/Deserlizer) is applied during read time to extract the required columns (late binding) – New data can start flowing anytime and will appear retroactively once the SerDe is updated to parse it. ...
... – Data is simply copied to the file store, no transformation is needed. – A SerDe (Serializer/Deserlizer) is applied during read time to extract the required columns (late binding) – New data can start flowing anytime and will appear retroactively once the SerDe is updated to parse it. ...
How is database integrity assured within the relational database
... What is a weak entity, and how is it represented in an E-R diagram? Give an example. How is a composite entity represented in an E-R diagram, and what is its function? Given the following business rules, create the appropriate E-R diagram for each of the specified relationships What three (often con ...
... What is a weak entity, and how is it represented in an E-R diagram? Give an example. How is a composite entity represented in an E-R diagram, and what is its function? Given the following business rules, create the appropriate E-R diagram for each of the specified relationships What three (often con ...
Study Guide for Mid
... Evaluating the primary key (determine if a surrogate key should be used) ...
... Evaluating the primary key (determine if a surrogate key should be used) ...
Characteristic of data record in relation
... • The notion "relational" is motivated by the mathematical concept of a relation. Relations in mathematics are sets of tuples. • Relational databases are collections of one or more relations. • In practice, relations can be visualized as tables, the rows of which are individual records of data with ...
... • The notion "relational" is motivated by the mathematical concept of a relation. Relations in mathematics are sets of tuples. • Relational databases are collections of one or more relations. • In practice, relations can be visualized as tables, the rows of which are individual records of data with ...
Functional Dependency
... instead of using a copy. Then updating the address in one place will instantly change all the places where the address is used. ...
... instead of using a copy. Then updating the address in one place will instantly change all the places where the address is used. ...
2 - CWI Amsterdam
... temp1 = account depositor at S2. Ship temp1 from S2 to S3, and compute temp2 = temp1 branch at S3. Ship the result temp2 to SI. • Devise similar strategies, exchanging the roles S1, S2, S3 ...
... temp1 = account depositor at S2. Ship temp1 from S2 to S3, and compute temp2 = temp1 branch at S3. Ship the result temp2 to SI. • Devise similar strategies, exchanging the roles S1, S2, S3 ...
Introduction to the Relational Model and SQL
... contents (database state) must satisfy in addition to the basic structure prescribed by the columns. • Constraints are declared as part of the database schema. • More than one key can be declared for a table More keys? One could, for example, discuss whether DNAME should also be a key (in addition t ...
... contents (database state) must satisfy in addition to the basic structure prescribed by the columns. • Constraints are declared as part of the database schema. • More than one key can be declared for a table More keys? One could, for example, discuss whether DNAME should also be a key (in addition t ...
Supporting Search-As-You-Type Using SQL in Databases
... We discuss the methods that use SQL to scan a table and verify each record by calling a userdefined function (UDF) or using the LIKE predicate. We study how to support fuzzy search for single-keyword queries. We discuss a gram-based method and a UDF-based method. As the two methods have a low perfor ...
... We discuss the methods that use SQL to scan a table and verify each record by calling a userdefined function (UDF) or using the LIKE predicate. We study how to support fuzzy search for single-keyword queries. We discuss a gram-based method and a UDF-based method. As the two methods have a low perfor ...
CIS560-Lecture-04-20080130 - Kansas State University
... Structure of Relational Databases Fundamental Relational-Algebra-Operations Additional Relational-Algebra-Operations Extended Relational-Algebra-Operations ...
... Structure of Relational Databases Fundamental Relational-Algebra-Operations Additional Relational-Algebra-Operations Extended Relational-Algebra-Operations ...
Introduction to SQL - Community College of Philadelphia
... In addition to the SELECT, FROM, and WHERE, clauses, several extension clauses can be added to the statement to modify how it works, including the following: ORDER BY - Sorts the rows in the result according to specified criteria GROUP BY – allows categorization of the results by a particular attrib ...
... In addition to the SELECT, FROM, and WHERE, clauses, several extension clauses can be added to the statement to modify how it works, including the following: ORDER BY - Sorts the rows in the result according to specified criteria GROUP BY – allows categorization of the results by a particular attrib ...
Chapter 13: Query Processing
... A6 (primary index, comparison). For A V(r) use index to find first tuple v and scan relation sequentially from there For AV (r) just scan relation sequentially till first tuple > v; – Using the index would be useless, and would requires extra seeks on the index file A7 (secondary inde ...
... A6 (primary index, comparison). For A V(r) use index to find first tuple v and scan relation sequentially from there For AV (r) just scan relation sequentially till first tuple > v; – Using the index would be useless, and would requires extra seeks on the index file A7 (secondary inde ...
Database System Concepts - Chapter 13: Query
... To compute r ⋊ ⋉θ s for each tuple tr in r do for each tuple ts in s do test pair (tr , ts ) for the join condition θ if θ is satisfied, add (tr , ts ) to the result end end r is called the outer relation and s the inner relation of the join Requires no indices and can be used with any kind of join ...
... To compute r ⋊ ⋉θ s for each tuple tr in r do for each tuple ts in s do test pair (tr , ts ) for the join condition θ if θ is satisfied, add (tr , ts ) to the result end end r is called the outer relation and s the inner relation of the join Requires no indices and can be used with any kind of join ...
Chapter13. Query Processing
... every block of outer relation. for each block Br of r do begin for each block Bs of s do begin for each tuple tr in Br do begin for each tuple ts in Bs do begin Check if (tr,ts) satisfy the join condition if they do, add tr • ts to the result. ...
... every block of outer relation. for each block Br of r do begin for each block Bs of s do begin for each tuple tr in Br do begin for each tuple ts in Bs do begin Check if (tr,ts) satisfy the join condition if they do, add tr • ts to the result. ...
Chapter 9
... Linkages (>1 table) No explicit pointers are present. The data are viewed as a collection of independent tables. Relations are formed by an attribute that is common to both tables in the relation. Assignment of foreign keys: if 1 to many association, the primary key on the one side is embedde ...
... Linkages (>1 table) No explicit pointers are present. The data are viewed as a collection of independent tables. Relations are formed by an attribute that is common to both tables in the relation. Assignment of foreign keys: if 1 to many association, the primary key on the one side is embedde ...
Parallel Databases
... Pi,j computes the join of ri with sj. In order to do so, ri is replicated to Pi,0, Pi,1, ..., Pi,m-1, while si is replicated to P0,i, P1,i, ..., Pn-1,i ...
... Pi,j computes the join of ri with sj. In order to do so, ri is replicated to Pi,0, Pi,1, ..., Pi,m-1, while si is replicated to P0,i, P1,i, ..., Pn-1,i ...
IT344TestBankandMultipleChoiceQuestions (1)
... 19.21 Suppose you have to compute A Gsum(C ) (r) as well as A,B Gsum(C ) (r). Describe how to compute these together using a single sorting of r. 19.22 Consider a relation r(A, B, C), with an index on attribute A. Give an example of a query that can answered using the index only, without looking at ...
... 19.21 Suppose you have to compute A Gsum(C ) (r) as well as A,B Gsum(C ) (r). Describe how to compute these together using a single sorting of r. 19.22 Consider a relation r(A, B, C), with an index on attribute A. Give an example of a query that can answered using the index only, without looking at ...
進階資料庫系統 課程綱要表 課程名稱： (中文) 進階資料庫系統 (英文
... This course will help students not only to achieve the following objectives: 1. Learn new ways to model data. 2. Learn and implement a DBMS. 3. Become familiar with the expanding role of database technology. but also: 4. Home works, midterm exam, final exam and final project are required. 5. Reading ...
... This course will help students not only to achieve the following objectives: 1. Learn new ways to model data. 2. Learn and implement a DBMS. 3. Become familiar with the expanding role of database technology. but also: 4. Home works, midterm exam, final exam and final project are required. 5. Reading ...
RAJALAKSHMI ENGINEERING COLLEGE
... 12. An entity set that does not have sufficient attributes to form a primary key is a (A) Strong entity set. (B) Weak entity set. (C) Simple entity set. (D) Primary entity set. 13 .In a Hierarchical model records are organized as (A) Graph. (B) List. (C) Links. (D) Tree. 14 .In an E-R diagram attrib ...
... 12. An entity set that does not have sufficient attributes to form a primary key is a (A) Strong entity set. (B) Weak entity set. (C) Simple entity set. (D) Primary entity set. 13 .In a Hierarchical model records are organized as (A) Graph. (B) List. (C) Links. (D) Tree. 14 .In an E-R diagram attrib ...
mod-19
... Pi,j computes the join of ri with sj. In order to do so, ri is replicated to Pi,0, Pi,1, ..., Pi,m-1, while si is replicated to P0,i, P1,i, ..., Pn-1,i ...
... Pi,j computes the join of ri with sj. In order to do so, ri is replicated to Pi,0, Pi,1, ..., Pi,m-1, while si is replicated to P0,i, P1,i, ..., Pn-1,i ...
COURSE OUTLINE HCS 206- MODELS OF DATABASE AND
... Relational algebra and operations in relational algebra SQL Structure of the SQL expression i.e. select clause; where clause; from clause Creating databases, tables and performing various operations using SQL statements Integrity and Security Types of integrity i.e. referential integrity ...
... Relational algebra and operations in relational algebra SQL Structure of the SQL expression i.e. select clause; where clause; from clause Creating databases, tables and performing various operations using SQL statements Integrity and Security Types of integrity i.e. referential integrity ...
Database as Model - UMD Department of Computer Science
... – No makeup exams. Exceptions as above. – Cheating will result in an immediate grade of XF ("failure through academic dishonesty" -- this goes on your permanent transcript), and may result in suspension or expulsion from University. This is your only warning. Don't do it. ...
... – No makeup exams. Exceptions as above. – Cheating will result in an immediate grade of XF ("failure through academic dishonesty" -- this goes on your permanent transcript), and may result in suspension or expulsion from University. This is your only warning. Don't do it. ...
Rel model/ER transform lecture
... an entry at each row & column intersection is single-valued (atomic) each row is unique Each attribute within a table has a unique name sequence of columns from left to right is insignificant sequence of rows from top to bottom is insignificant ...
... an entry at each row & column intersection is single-valued (atomic) each row is unique Each attribute within a table has a unique name sequence of columns from left to right is insignificant sequence of rows from top to bottom is insignificant ...
Structured Query Language SQL
... SQL (Structured Query Language) is a query language for relational databases. The roots of SQL go back to SQUARE, a more mathematical oriented language and SEQUEL, a predecessor of SQL from the seventies. There exist different standards (ISO and ANSI) of SQL, but the most common one is SQL-92. The l ...
... SQL (Structured Query Language) is a query language for relational databases. The roots of SQL go back to SQUARE, a more mathematical oriented language and SEQUEL, a predecessor of SQL from the seventies. There exist different standards (ISO and ANSI) of SQL, but the most common one is SQL-92. The l ...