What is Data Model?

What is Data Model?
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1 Answer

Answer :

A collection of conceptual tools for describing data, data relationships data semantics and  constraints.
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Related questions

Is it possible to insert comments into sql statements return in the data model editor?

Description : Is it possible to insert comments into sql statements return in the data model editor?

Last Answer : Yes

Why is it preferable to create a fewer no. of queries in the data model?

Description : Why is it preferable to create a fewer no. of queries in the data model?

Last Answer : Because for each query, report has to open a separate cursor and has to rebind, execute and fetch data.

Atleast how many set of data must a data model have before a data model can be base on it?

Description : Atleast how many set of data must a data model have before a data model can be base on it?

Last Answer : Four

Does a grouping done for objects in the layout editor affect the grouping done in the data model editor?

Description : Does a grouping done for objects in the layout editor affect the grouping done in the data model editor?

Last Answer : No.

If two groups are not linked in the data model editor, What is the hierarchy between them?

Description : If two groups are not linked in the data model editor, What is the hierarchy between them?

Last Answer : Two group that is above are the left most rank higher than the group that is to right or below it.

What is Object Oriented model?

Description : What is Object Oriented model?

Last Answer : This model is based on collection of objects. An object contains values stored in instance variables with in the object. An object also contains bodies of code that operate on the object. These ... . Objects that contain same types of values and the same methods are grouped together into classes.

What is E-R model?

Description : What is E-R model?

Last Answer : This data model is based on real world that consists of basic objects called entities and of relationship among these objects. Entities are described in a database by a set of attributes.

The Relational Model Database:

Description : The Relational Model Database:

Last Answer : The relational model is the most popular type of database and an extremely powerful tool, not only to store information, but to access it as well. Relational databases are organized as tables. The ... reorganizing the tables. A table can have many records and each record can have many fields.

The Network Model Database:

Description : The Network Model Database:

Last Answer : In a network model, the defining feature is that a record is stored with a link to other records – in effect networked. These networks (or sometimes referred to as pointers) can be a variety of different types of information such as node numbers or even a disk address.

The Hierarchical Model Database:

Description : The Hierarchical Model Database:

Last Answer : The hierarchical model database resembles a tree like structure, such as how Microsoft Windows organizes folders and files. In a hierarchical model database, each upward link is nested in order to keep data ... Within this nested file are all of the sales (same types of data) for the day.

The Flat Model Database:

Description : The Flat Model Database:

Last Answer : In a flat model database, there is a two dimensional (flat structure) array of data. For instance, there is one column of information and within this column it is assumed that each data item will be related ... will only be one column and each new row within that one column will be a new zip code.

Can a repeating frame be created without a data group as a base?

Description : Can a repeating frame be created without a data group as a base?

Last Answer : No

Can one resize tablespaces and data files? (for DBA)

Description : Can one resize tablespaces and data files? (for DBA)

Last Answer : One can manually increase or decrease the size of a datafile from Oracle 7.2 using the command. ALTER DATABASE DATAFILE 'filename2' RESIZE 100M; Because you can change the ... UNLIMITED DEFAULT STORAGE (INITIAL 10240 NEXT 10240 MINEXTENTS 1 MAXEXTENTS UNLIMITED PCTINCREASE 0) ONLINE PERMANENT;

What view would you use to look at the size of a data file?

Description : What view would you use to look at the size of a data file?

Last Answer : DBA_DATA_FILES

How do you resize a data file?

Description : How do you resize a data file?

Last Answer : ALTER DATABASE DATAFILE RESIZE ;

How do you add a data file to a tablespace

Description : How do you add a data file to a tablespace

Last Answer : ALTER TABLESPACE ADD DATAFILE SIZE

Give the two types of tables involved in producing a star schema and the type of data they hold.

Description : Give the two types of tables involved in producing a star schema and the type of data they hold.

Last Answer : Fact tables and dimension tables. A fact table contains measurements while dimension tables will contain data that will help describe the fact tables.

Explain the difference between a data block, an extent and a segment.

Description : Explain the difference between a data block, an extent and a segment.

Last Answer : A data block is the smallest unit of logical storage for a database object. As objects grow they take chunks of additional storage that are composed of contiguous data blocks. These groupings ... that an object takes when grouped together are considered the segment of the database object.

The join defined by the default data link is an outer join yes or no?

Description : The join defined by the default data link is an outer join yes or no?

Last Answer : Yes

Can a field be used in a report without it appearing in any data group?

Description : Can a field be used in a report without it appearing in any data group?

Last Answer : Yes

For a field in a repeating frame, can the source come from the column which does not exist in the data group which forms the base for the frame?

Description : For a field in a repeating frame, can the source come from the column which does not exist in the data group which forms the base for the frame?

Last Answer : Yes

What are the characteristics of data files?

Description : What are the characteristics of data files?

Last Answer : A data file can be associated with only one database. Once created a data file can't change size. One or more data files form a logical unit of database storage called a tablespace.

What is a data segment?

Description : What is a data segment?

Last Answer : Each non-clustered table has a data segment. All of the table's data is stored in the extents of its data segment. Each cluster has a data segment. The data of every table in the cluster is stored in the cluster's data segment.

How to define data block size?

Description : How to define data block size?

Last Answer : A data block size is specified for each Oracle database when the database is created. A database users and allocated free database space in Oracle data blocks. Block size is specified in init.ora file and cannot be changed latter.

What is data block?

Description : What is data block?

Last Answer : Oracle database's data is stored in data blocks. One data block corresponds to a specific number of bytes of physical database space on disk.

Physical Storage of the Data

Description : Physical Storage of the Data

Last Answer : The finest level of granularity of the data base are the data blocks. Data Block :: One Data Block correspond to specific number of physical database space Extent :: Extent is the number of ... Index has index segment that stores data c) Roll Back Segment :: Temporarily store 'undo' information

Table Space,Data Files,Parameter File, Control Files

Description : Table Space,Data Files,Parameter File, Control Files

Last Answer : Table Space :: The table space is useful for storing the data in the database.When a database is created two table spaces are created. a) System Table space :: This data file stores all the tables ... They contain the Db name, name and location of dbs, data files ,redo log files and time stamp.

What are the data types allowed in a table ?

Description : What are the data types allowed in a table ?

Last Answer : CHAR,VARCHAR2,NUMBER,DATE,RAW,LONG and LONG RAW.

Where the integrity constraints are stored in Data Dictionary ?

Description : Where the integrity constraints are stored in Data Dictionary ?

Last Answer : The integrity constraints are stored in USER_CONSTRAINTS.

Difference between NO DATA FOUND and %NOTFOUND?

Description : Difference between NO DATA FOUND and %NOTFOUND?

Last Answer : NO DATA FOUND is an exception raised only for the SELECT....INTO statements when the where clause of the querydoes not match any rows. When the where clause of the explicit cursor does not match any rows the %NOTFOUND attribute is set to TRUE instead.

What should be the return type for a cursor variable.Can we use a scalar data type as return type?

Description : What should be the return type for a cursor variable.Can we use a scalar data type as return type?

Last Answer : The return type for a cursor must be a record type.It can be declared explicitly as a user-defined or %ROWTYPE can be used. eg TYPE t_studentsref IS REF CURSOR RETURN students%ROWTYPE

It is possible to use raw devices as data files and what is the advantages over file. system files ?

Description : It is possible to use raw devices as data files and what is the advantages over file. system files ?

Last Answer : Yes. The advantages over file system files. I/O will be improved because Oracle is bye-passing the kernnel which writing into disk. Disk Corruption will be very less.

What are the two ways by which data can be generated for a parameters list of values?

Description : What are the two ways by which data can be generated for a parameters list of values?

Last Answer : 1. Using static values. 2. Writing select statement.

Can you pass data parameters to forms?

Description : Can you pass data parameters to forms?

Last Answer : No

Do user parameters appear in the data modal editor in 2.5?

Description : Do user parameters appear in the data modal editor in 2.5?

Last Answer : No

Does Oracle write to data files in begin/hot backup mode? (for DBA

Description : Does Oracle write to data files in begin/hot backup mode? (for DBA

Last Answer : Oracle will stop updating file headers, but will continue to write data to the database files even if a tablespace is in backup mode.In backup mode, Oracle will write out complete changed blocks ... ). Because of this, one should notice increased log activity and archiving during on-line backups.

What is the basic data structure that is required for creating an LOV?

Description : What is the basic data structure that is required for creating an LOV?

Last Answer : Record Group.

When do you use data parameter type?

Description : When do you use data parameter type?

Last Answer : When the value of a data parameter being passed to a called product is always the name of the record group defined in the current form. Data parameters are used to pass data to produts invoked with the run_product built-in subprogra

Do a view contain data?

Description : Do a view contain data?

Last Answer : Views do not contain or store data.

What is a data segment?

Description : What is a data segment?

Last Answer : Data segment are the physical areas within a database block in which the data associated with tables and clusters are stored.

What dynamic data replication?

Description : What dynamic data replication?

Last Answer : Updating or Inserting records in remote database through database triggers. It may fail if remote database is having any problem.

When will the data in the snapshot log be used?

Description : When will the data in the snapshot log be used?

Last Answer : We must be able to create a after row trigger on table (i.e., it should be not be already available) After giving table privileges. We cannot specify snapshot log name because oracle uses the ... 23 characters. (The table name created will be MLOGS_tablename, and trigger name will be TLOGS name).

How to define Data Block size ?

Description : How to define Data Block size ?

Last Answer : A data block size is specified for each ORACLE database when the database is created. A database users and allocated free database space in ORACLE datablocks. Block size is specified in INIT.ORA file and can’t be changed latter.

What are the Characteristics of Data Files ?

Description : What are the Characteristics of Data Files ?

Last Answer : A data file can be associated with only one database. Once created a data file can't change size. One or more data files form a logical unit of database storage called a tablespace.

Explain the relationship among Database, Tablespace and Data file.?

Description : Explain the relationship among Database, Tablespace and Data file.?

Last Answer : Each databases logically divided into one or more tablespaces one or more data files are explicitly created for each tablespace

Do View contain Data ?

Description : Do View contain Data ?

Last Answer : Views do not contain or store data.

Explain the relationship among database, tablespace and data file.

Description : Explain the relationship among database, tablespace and data file.

Last Answer : Each databases logically divided into one or more tablespaces one or more data files are explicitly created for each tablespace.

What do you understand by Reference Data Sharing?

Description : What do you understand by Reference Data Sharing?

Last Answer : In oracle Fusion Reference data sharing facilitates sharing of configuration data such as jobs, grades across business units. It can be understood as buckets of reference data assigned to ... where appropriate. In Oracle Fusion Applications reference data sharing feature is also known as SetID

What is Legislative Data Group in Fusion HCM?

Description : What is Legislative Data Group in Fusion HCM?

Last Answer : Legislative data groups are a means of partitioning payroll and related data. At least one legislative data group is required for each country where the enterprise operates. Each legislative data group ... and is associated with a legislative code, currency and its own cost key flexfield structure.

What is the job of the information stored in data-dictionary?

Description : What is the job of the information stored in data-dictionary?

Last Answer : The information in the data dictionary validates the existence of the objects, provides access to them, and maps the actual physical storage location.