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A DATA WAREHOUSE is for the enterprise and contains multiple subjects. A data mart is for a specific functional area and focuses on ONE SUBJECT. A data warehouse is flexible and data-oriented and contains detailed historical data. A data mart is restrictive and project-oriented and contains some historical data.

A data warehouse is for the enterprise and contains multiple subjects. A data mart is for a specific functional area and focuses on one subject. A data warehouse is flexible and data-oriented and contains detailed historical data. A data mart is restrictive and project-oriented and contains some historical data.

One reason that an information gap exists is the fact that systems have been DEVELOPED in separate, SEGMENTED efforts. This has helped the data from being stored in an integrated database and thus the data is in an inconsistent structure. The other reason for the gap is that most systems are created to SUPPORT the operational ASPECT of an ORGANIZATION. The systems were not developed for decision making.

One reason that an information gap exists is the fact that systems have been developed in separate, segmented efforts. This has helped the data from being stored in an integrated database and thus the data is in an inconsistent structure. The other reason for the gap is that most systems are created to support the operational aspect of an organization. The systems were not developed for decision making.

A DATA warehouse is organized around specific subjects. The data is defined USING consistent naming, format, and encoding structure standards. The data contains a time element, so that the data can be STUDIED for trends. No data in a data warehouse can be updated by end USERS.

A data warehouse is organized around specific subjects. The data is defined using consistent naming, format, and encoding structure standards. The data contains a time element, so that the data can be studied for trends. No data in a data warehouse can be updated by end users.

Website security issues include unauthorized ACCESS to the several aspects of one’s Website. Security MEASURES should include all aspects of the system such as the network, operating level, DATABASE, and Web server. Regular MONITORING and security testing by a company should help to avoid intrusion into one’s system.

Website security issues include unauthorized access to the several aspects of one’s Website. Security measures should include all aspects of the system such as the network, operating level, database, and Web server. Regular monitoring and security testing by a company should help to avoid intrusion into one’s system.

XML Is used to structure and manipulate data involved with a BROWSER and is becoming the standard for ec ommerce. XML uses tags that are similar to HTML in that they use the angle brackets, but XML describes the CONTENT WHEREAS HTML describes the appearance. The XML schema standard was PUBLISHED in May 2001 by W3C.

XML Is used to structure and manipulate data involved with a browser and is becoming the standard for ec ommerce. XML uses tags that are similar to HTML in that they use the angle brackets, but XML describes the content whereas HTML describes the appearance. The XML schema standard was published in May 2001 by W3C.

Web Services are IMPROVING the ABILITY of computers to communicate over the Internet. These services use XML programs and usually run in the background. Easier integration of applications may be possible because developers do not need to be FAMILIAR with the technical details with applications that are being integrated. UDDI is a technical specification for creating a distributed registry of Web services and businesses that are open to COMMUNICATING through Web services.

Web Services are improving the ability of computers to communicate over the Internet. These services use XML programs and usually run in the background. Easier integration of applications may be possible because developers do not need to be familiar with the technical details with applications that are being integrated. UDDI is a technical specification for creating a distributed registry of Web services and businesses that are open to communicating through Web services.

Both ASP and ColdFusion are MIDDLEWARE that ease the connection of databases to Web applications. Both require the use of several files. Both use TAGS and are executed on the server. Both INTERNET Explorer and Netscape can ACCESS these files. The PROGRAMMER does not need to be concerned with the client when they work with this middleware.

Both ASP and ColdFusion are middleware that ease the connection of databases to Web applications. Both require the use of several files. Both use tags and are executed on the server. Both Internet Explorer and Netscape can access these files. The programmer does not need to be concerned with the client when they work with this middleware.

You can perform more COMPLEX functions and error handling can be accommodated by VBA. VBA code will execute faster since code runs faster than MACROS and maintenance is easier because VBA modules are stored with the forms and reports. Reading VBA is easier because you can SEE the entire code. Finally, you can pass PARAMETERS and USE OLE automation better.

You can perform more complex functions and error handling can be accommodated by VBA. VBA code will execute faster since code runs faster than macros and maintenance is easier because VBA modules are stored with the forms and reports. Reading VBA is easier because you can see the entire code. Finally, you can pass parameters and use OLE automation better.

A fat client is a PC that is responsible where most processing OCCURS on the client rather than the server. Some of the fat client ACTIVITIES include processing, PRESENTATION logic, and business rules logic. A THIN client is a PC where only LIMITED processing occurs. In these cases, more processing should occur on the application server.

A fat client is a PC that is responsible where most processing occurs on the client rather than the server. Some of the fat client activities include processing, presentation logic, and business rules logic. A thin client is a PC where only limited processing occurs. In these cases, more processing should occur on the application server.

ODBC is a standard that contains an interface that provides a common LANGUAGE for application programs to ACCESS and process SQL databases. In order to use ODBC, a driver, server name, DATABASE name, user id, and password are required. ODBC is important for INTERNET applications and has gained wide acceptance.

ODBC is a standard that contains an interface that provides a common language for application programs to access and process SQL databases. In order to use ODBC, a driver, server name, database name, user id, and password are required. ODBC is important for Internet applications and has gained wide acceptance.

QBE is a direct-manipulation database language that uses a graphical approach to query construction. Some database systems translate QBE QUERIES into SQL. QBE does not adhere to a standard but SQL does. Both SQL and QBE are RELATIONAL database languages.

QBE is a direct-manipulation database language that uses a graphical approach to query construction. Some database systems translate QBE queries into SQL. QBE does not adhere to a standard but SQL does. Both SQL and QBE are relational database languages.

A three-tier architecture includes a client and two server LAYERS. The APPLICATION code is STORED on the application server and the database is stored on the database server. A two-tier architecture includes a client and ONE server layer. The database is stored on the database server.

A three-tier architecture includes a client and two server layers. The application code is stored on the application server and the database is stored on the database server. A two-tier architecture includes a client and one server layer. The database is stored on the database server.

Embedded SQL is the PROCESS of INCLUDING hard coded SQL statements. These statements do not CHANGE UNLESS the source code is MODIFIED. Dynamic SQL is the process of generating SQL on the fly. The statements generated do not have to be the same each time.

Embedded SQL is the process of including hard coded SQL statements. These statements do not change unless the source code is modified. Dynamic SQL is the process of generating SQL on the fly. The statements generated do not have to be the same each time.

A subquery is a query that is composed of two queries. The first query (inner query) is within the WHERE clause of the other query (OUTER query). In some cases the inner query provides RESULTS for the outer query to PROCESS. In other cases, the outer query results provide results for the inner query (correlated subquery).

A subquery is a query that is composed of two queries. The first query (inner query) is within the WHERE clause of the other query (outer query). In some cases the inner query provides results for the outer query to process. In other cases, the outer query results provide results for the inner query (correlated subquery).

An outer join includes the records that MATCH and those that do not have a matching value in ANOTHER table. Outer JOINS can be a LEFT outer join (includes all records from the FIRST table listed) or a RIGHT outer join (includes all records from the second table listed). Outer joins are not easily used with more than two tables.

An outer join includes the records that match and those that do not have a matching value in another table. Outer joins can be a LEFT outer join (includes all records from the first table listed) or a RIGHT outer join (includes all records from the second table listed). Outer joins are not easily used with more than two tables.

Triggers are stored and controlled in the DBMS. A trigger is executed AUTOMATICALLY when a CONDITION is met (INSERT, UPDATE, or DELETE). A procedure is also stored in a DATABASE. A procedure is not executed automatically.

Triggers are stored and controlled in the DBMS. A trigger is executed automatically when a condition is met (INSERT, UPDATE, or DELETE). A procedure is also stored in a database. A procedure is not executed automatically.

A standard language can HINDER the effort to create a new language. One standard is never enough to MEET all of the BUSINESS needs. A standard can be a compromise among interested PARTIES which can cause the standard to not be ideal. If a standard is altered by some, than PORTABILITY between platforms could be hurt.

A standard language can hinder the effort to create a new language. One standard is never enough to meet all of the business needs. A standard can be a compromise among interested parties which can cause the standard to not be ideal. If a standard is altered by some, than portability between platforms could be hurt.

1. Identify the data type, LENGTH, and precision for each attribute.

2. Identify the columns that can ACCEPT a null value.

3. Identify the columns that need to be unique.

4. Identify primary and related FOREIGN KEYS with the parent table being created before the child.

5. Determine default values.

6. Determine where the DOMAIN values are that need to be constrained.

7. Create the indexes.

1. Identify the data type, length, and precision for each attribute.

2. Identify the columns that can accept a null value.

3. Identify the columns that need to be unique.

4. Identify primary and related foreign keys with the parent table being created before the child.

5. Determine default values.

6. Determine where the domain values are that need to be constrained.

7. Create the indexes.

Data DEFINITION language COMMANDS are USED to create, alter, and drop tables. Data manipulation commands are used to insert, modify, update, and query data in the DATABASE. Data control language commands help the DBA to control the database.

Data definition language commands are used to create, alter, and drop tables. Data manipulation commands are used to insert, modify, update, and query data in the database. Data control language commands help the DBA to control the database.

Choosing primary and secondary keys can increase the speed of ROW SELECTION, JOINING, and row ordering. Selecting the appropriate file organization for base tables and INDEXES can also improve performance. Clustering related rows together and maintaining statistics about tables and indexes can lead to increased EFFICIENCY.

Choosing primary and secondary keys can increase the speed of row selection, joining, and row ordering. Selecting the appropriate file organization for base tables and indexes can also improve performance. Clustering related rows together and maintaining statistics about tables and indexes can lead to increased efficiency.

A DYNAMIC view may be created every time that a specific view is requested by a user. A materialized view is created and or updated infrequently and it MUST be synchronized with its ASSOCIATED base table(s).

A dynamic view may be created every time that a specific view is requested by a user. A materialized view is created and or updated infrequently and it must be synchronized with its associated base table(s).

Horizontal portioning is where the ROWS in a relation are separated by some CRITERIA and placed into a NEW relation or file with the same layout as the ORIGINAL relation (in this case only the records in each file differ). Vertical portioning is where the columns in a relation are separated by some criteria and placed into a new relation or file with a different layout as the original relation.

Horizontal portioning is where the rows in a relation are separated by some criteria and placed into a new relation or file with the same layout as the original relation (in this case only the records in each file differ). Vertical portioning is where the columns in a relation are separated by some criteria and placed into a new relation or file with a different layout as the original relation.

A data type should be selected so that all possible VALUES are represented using MINIMAL STORAGE space. The data type should HELP to ensure data integrity and support all possible data manipulations (i.e., cannot place a letter in a field such as SALARY where a number is required).

A data type should be selected so that all possible values are represented using minimal storage space. The data type should help to ensure data integrity and support all possible data manipulations (i.e., cannot place a letter in a field such as salary where a number is required).

Domain constraints include entity integrity and REFERENTIAL integrity. The domain is a SET of values that may be assigned to an attribute. The entity integrity rule states that no part of a primary key cannot be NULL. Referential integrity states that each foreign key value must MATCH a primary key value or be null.

Domain constraints include entity integrity and referential integrity. The domain is a set of values that may be assigned to an attribute. The entity integrity rule states that no part of a primary key cannot be null. Referential integrity states that each foreign key value must match a primary key value or be null.

A SEPARATE RELATION is created for each supertype and subtype. The attributes common for all of the subtypes are assigned to the supertype. Each subtype has the PRIMARY key from the supertype assigned to it. A subtype DISCRIMINATOR is added to the supertype.

A separate relation is created for each supertype and subtype. The attributes common for all of the subtypes are assigned to the supertype. Each subtype has the primary key from the supertype assigned to it. A subtype discriminator is added to the supertype.

First you MUST verify that a relation is in both first normal form and second normal form. If the relation is not, you must convert into second normal form. After a relation is in second normal form, you must remove all TRANSITIVE DEPENDENCIES.

First you must verify that a relation is in both first normal form and second normal form. If the relation is not, you must convert into second normal form. After a relation is in second normal form, you must remove all transitive dependencies.

Relations in a DATABASE have a unique name and no multivalued attributes exist. Each ROW is unique and each attribute WITHIN a relation has a unique name. The sequence of both COLUMNS and rows is irrelevant.

Relations in a database have a unique name and no multivalued attributes exist. Each row is unique and each attribute within a relation has a unique name. The sequence of both columns and rows is irrelevant.

Normalization should MINIMIZE data redundancy. It should ALSO simplify referential integrity constraints. Normalization will also make it EASIER to insert, update, and delete data. And finally, it provides better design.

Normalization should minimize data redundancy. It should also simplify referential integrity constraints. Normalization will also make it easier to insert, update, and delete data. And finally, it provides better design.

A scenario is used to test business RULES. It is a short SCRIPT that describes how a business REACTS to certain situations.

A scenario is used to test business rules. It is a short script that describes how a business reacts to certain situations.

A derivation is a STATEMENT that is derived from other knowledge. A structured ASSERTION is a statement that expresses some aspect of the static STRUCTURE of an organization. An ACTION assertion is a statement of a constraint on the ACTIONS of an organization.

A derivation is a statement that is derived from other knowledge. A structured assertion is a statement that expresses some aspect of the static structure of an organization. An action assertion is a statement of a constraint on the actions of an organization.

The disjoint rule states an ENTITY instance of a SUPERTYPE can only be a MEMBER of one SUBTYPE.
The overlap rule states an entity instance of a supertype can be a member of multiple subtypes.

The disjoint rule states an entity instance of a supertype can only be a member of one subtype.
The overlap rule states an entity instance of a supertype can be a member of multiple subtypes.

An EER includes everything in an ERD and an EER allows for more complex relationships than an ERD. An EER allows for object-oriented DATA MODELING and INCLUDE supertypes and subtypes entities and inheritance.

An EER includes everything in an ERD and an EER allows for more complex relationships than an ERD. An EER allows for object-oriented data modeling and include supertypes and subtypes entities and inheritance.

TOTAL specialization EXISTS when every instance of a supertype must ALSO be an instance of a subtype. Partial specialization exists when every instance of a supertype does not have to be an instance of a subtype.

Total specialization exists when every instance of a supertype must also be an instance of a subtype. Partial specialization exists when every instance of a supertype does not have to be an instance of a subtype.

The values of data MAY change. A TIME STAMP helps to ensure that the previous VALUE of the data stays in the database after it has changed so that you can see the before and after values through time. Without a time stamp, you will most likely lose some of the history.

The values of data may change. A time stamp helps to ensure that the previous value of the data stays in the database after it has changed so that you can see the before and after values through time. Without a time stamp, you will most likely lose some of the history.

Minimum cardinality is the minimum number of INSTANCES of an ENTITY that can be ASSOCIATED with each INSTANCE of another entity. Maximum cardinality is the maximum number of instances of an entity that can be associated with each instance of another entity.

Minimum cardinality is the minimum number of instances of an entity that can be associated with each instance of another entity. Maximum cardinality is the maximum number of instances of an entity that can be associated with each instance of another entity.

Definitions are gathered from the same SOURCES and should be accompanied DIAGRAMS. A definition will include special conditions, EXAMPLES, how the data is CREATED, WHETHER the data can change, who owns the data, whether the data is optional, and whether the data can be broken into something more atomic.

Definitions are gathered from the same sources and should be accompanied diagrams. A definition will include special conditions, examples, how the data is created, whether the data can change, who owns the data, whether the data is optional, and whether the data can be broken into something more atomic.

An ERD is a DETAILED logical representation of the data for an ORGANIZATION. The ERD includes entities, ATTRIBUTES, relationships, and cardinalities. An ERD is the MECHANISM where an entity-relationship model is displayed.

An ERD is a detailed logical representation of the data for an organization. The ERD includes entities, attributes, relationships, and cardinalities. An ERD is the mechanism where an entity-relationship model is displayed.

UNIVERSAL DATA MODELS are common to many organizations. These models may be useful for similar functions that are used across companies or organizations such as purchasing and accounting. Industry-SPECIFIC data models are used by specific INDUSTRIES.

Universal data models are common to many organizations. These models may be useful for similar functions that are used across companies or organizations such as purchasing and accounting. Industry-specific data models are used by specific industries.

Databases can support from a SINGLE user (personal DATABASE) up to supporting the requests of the world (INTERNET database). In between, a database can support a workgroup (a relatively small group of people), department database (a functional unit in an organization such as MARKETING), or an enterprise database (entire organization).

Databases can support from a single user (personal database) up to supporting the requests of the world (internet database). In between, a database can support a workgroup (a relatively small group of people), department database (a functional unit in an organization such as marketing), or an enterprise database (entire organization).

There are five disadvantages. Program-data dependence occurs when file descriptions need to be changed in all programs whenever a file description changes. Duplication of data is storing the data more than one time. Limited data SHARING occurs when the files are private so no one outside of one application can access the data. Lengthy DEVELOPMENT times EXIST because file PROCESSING systems takes longer to develop. Lastly, excessive program maintenance exists since the effort to MAINTAIN a program is larger in this environment.

There are five disadvantages. Program-data dependence occurs when file descriptions need to be changed in all programs whenever a file description changes. Duplication of data is storing the data more than one time. Limited data sharing occurs when the files are private so no one outside of one application can access the data. Lengthy development times exist because file processing systems takes longer to develop. Lastly, excessive program maintenance exists since the effort to maintain a program is larger in this environment.

Many BUSINESSES still use file processing systems today. This is especially true in the creation of backups for a database system. In addition, if you understand some of the limitations of a file processing system such as program-DATA dependence, duplication of data, limited data SHARING, lengthy development times, and excessive program maintenance, you can try and avoid them as you design and develop a DATABASES.

Many businesses still use file processing systems today. This is especially true in the creation of backups for a database system. In addition, if you understand some of the limitations of a file processing system such as program-data dependence, duplication of data, limited data sharing, lengthy development times, and excessive program maintenance, you can try and avoid them as you design and develop a databases.

Structured data are facts concerning objects and events. The most important structured data are numeric, character, and dates. Structured data are STORED in tabular form. UNSTRUCTURED data are multimedia data such as documents, photographs, maps, images, sound, and VIDEO clips. Unstructured data are most commonly FOUND on Web SERVERS and Web-enabled databases.

Structured data are facts concerning objects and events. The most important structured data are numeric, character, and dates. Structured data are stored in tabular form. Unstructured data are multimedia data such as documents, photographs, maps, images, sound, and video clips. Unstructured data are most commonly found on Web servers and Web-enabled databases.

Market basket analysis is a DATA mining technique that determines which sets of products tend to be purchased together. A common technique uses conditional PROBABILITIES. In addition to the basic probability that an item will be purchased, three results are of particular interest:
Support -- the probability of TWO items being purchased together. Confidence -- the probability of a second item being purchased GIVEN that another item has been purchased. Lift -- calculated as confidence divided by a basic probability, this SHOWS the likelihood of a second item being purchased IF an item is purchased.

Market basket analysis is a data mining technique that determines which sets of products tend to be purchased together. A common technique uses conditional probabilities. In addition to the basic probability that an item will be purchased, three results are of particular interest:
Support -- the probability of two items being purchased together. Confidence -- the probability of a second item being purchased GIVEN that another item has been purchased. Lift -- calculated as confidence divided by a basic probability, this shows the likelihood of a second item being purchased IF an item is purchased.

OnLine Analytical PROCESSING (OLAP) is a BUSINESS Intelligence (BI) reporting system. OLAP provides the user with the capability to sum, count, average and do other simple arithmetic operations on groups of data. An OLAP report has measures and dimensions. Measures are the data values to be displayed. Dimensions are CHARACTERISTICS of the measures. OLAP reports are called OLAP cubes, although such reports are not LIMITED to three dimensions.

OnLine Analytical Processing (OLAP) is a Business Intelligence (BI) reporting system. OLAP provides the user with the capability to sum, count, average and do other simple arithmetic operations on groups of data. An OLAP report has measures and dimensions. Measures are the data values to be displayed. Dimensions are characteristics of the measures. OLAP reports are called OLAP cubes, although such reports are not limited to three dimensions.

A reporting system has three functions: 1. Report authoring -- connecting to data sources, creating the report structure and formatting the report. 2. Report management -- defining who RECEIVES which reports, when they receive them and how the reports are DELIVERED. 3. Report delivery -- based on report management metadata, either pushing the reports to the RECIPIENTS or ALLOWING them to be pulled by the recipients.

A reporting system has three functions: 1. Report authoring -- connecting to data sources, creating the report structure and formatting the report. 2. Report management -- defining who receives which reports, when they receive them and how the reports are delivered. 3. Report delivery -- based on report management metadata, either pushing the reports to the recipients or allowing them to be pulled by the recipients.

A data mart Is a COLLECTION of data smaller In scope and size than a data warehouse. It is dedicated to data from a particular business component of business functional AREA. A data mart may function as a SUBSET of a larger data warehouse. Users of a data mart are usually knowledgeable analysts in the business area USING the data mart.

A data mart Is a collection of data smaller In scope and size than a data warehouse. It is dedicated to data from a particular business component of business functional area. A data mart may function as a subset of a larger data warehouse. Users of a data mart are usually knowledgeable analysts in the business area using the data mart.

MySQL USES integer data TYPES COMBINED with the property AUTO_INCREMENT to create surrogate keys. This creates a sequence that starts at one (1) and increases by one (2) for each new record. MySql maintain its metadata in a database named mysql. For EXAMPLE, this database maintains TWO tables named user and db.

MySQL uses integer data types combined with the property AUTO_INCREMENT to create surrogate keys. This creates a sequence that starts at one (1) and increases by one (2) for each new record. MySql maintain its metadata in a database named mysql. For example, this database maintains two tables named user and db.

Simple elements have only one data VALUE. ComplexType elements can have MULTIPLE elements NESTED within them. ComplexTypes may ALSO have attributes. The elements contained in a complexType may be simple or other complexTypes. ComplexTypes may also define ELEMENT sequences.

Simple elements have only one data value. ComplexType elements can have multiple elements nested within them. ComplexTypes may also have attributes. The elements contained in a complexType may be simple or other complexTypes. ComplexTypes may also define element sequences.

DTD (Document TYPE Declarations) and XML Schemas. An XML document that conforms to its DTD is CALLED type-valid. A document can be well-formed and not be type-valid, either because it violates the STRUCTURE of its DTD or because it has no DTD. However, DTD5 have LIMITATIONS and to overcome these limits XML Schemas were created. XML Schemas are XML DOCUMENTS that are the preferred method for defining document structure.

DTD (Document Type Declarations) and XML Schemas. An XML document that conforms to its DTD is called type-valid. A document can be well-formed and not be type-valid, either because it violates the structure of its DTD or because it has no DTD. However, DTD5 have limitations and to overcome these limits XML Schemas were created. XML Schemas are XML documents that are the preferred method for defining document structure.

XML is a BETTER MARKUP language than HTML, primarily because XML provides a clear separation between document STRUCTURE, content, and materialization. Symbols cannot be USED ambiguously with XML.

XML is a better markup language than HTML, primarily because XML provides a clear separation between document structure, content, and materialization. Symbols cannot be used ambiguously with XML.