PPT-Lesson 1 - Getting Started with a Database
... Types of databases: Relational – Access is a relational database; It’s the most common type of database; eliminates duplication of records Flat – Excel – each database is represented as a single table Hierarchical – data is organized into a tree-like structure Network – each record type ca ...
... Types of databases: Relational – Access is a relational database; It’s the most common type of database; eliminates duplication of records Flat – Excel – each database is represented as a single table Hierarchical – data is organized into a tree-like structure Network – each record type ca ...
Client/Server Programming Services White Paper
... Work’ concept in updating the database so that you never end up with transactions that are only partially updated. If any table update in the ‘Logical Unit of Work’ fails we rollback all of the table updates, and let you reapply your transaction. You are never out of balance or in an inconsistent st ...
... Work’ concept in updating the database so that you never end up with transactions that are only partially updated. If any table update in the ‘Logical Unit of Work’ fails we rollback all of the table updates, and let you reapply your transaction. You are never out of balance or in an inconsistent st ...
Sistem Basis Data
... • Update -> updates existing data within a table • Delete -> deletes all records from a table, the space for the records remain • Merge -> upsert operation (insert or update) • Call -> call a procedure language / SQL or java subprogram • Explain plan -> explain access path to data • Lock table -> co ...
... • Update -> updates existing data within a table • Delete -> deletes all records from a table, the space for the records remain • Merge -> upsert operation (insert or update) • Call -> call a procedure language / SQL or java subprogram • Explain plan -> explain access path to data • Lock table -> co ...
Database Languages - Vrije Universiteit Brussel
... The overhead involved should be balanced against the performance improvement . Guidelines: index the primary key if it is not the key of the file organization no indexes on small relations add secondary indexes on heavily used attributes add secondary indexes to a foreign key avoid keys on ...
... The overhead involved should be balanced against the performance improvement . Guidelines: index the primary key if it is not the key of the file organization no indexes on small relations add secondary indexes on heavily used attributes add secondary indexes to a foreign key avoid keys on ...
Training
... – Undo log records old values of all objects – Read/write logs, to check for interference ...
... – Undo log records old values of all objects – Read/write logs, to check for interference ...
Download
... SQL – QBE – QUEL – Basic structure – various Operations – Relational database design problems in the relational data base design – Normalisation – normalization using functional, Multi value and join dependencies. Unit III File and system structure – overall system structure – file Organization – da ...
... SQL – QBE – QUEL – Basic structure – various Operations – Relational database design problems in the relational data base design – Normalisation – normalization using functional, Multi value and join dependencies. Unit III File and system structure – overall system structure – file Organization – da ...
Data Design Rules
... Useful for limiting the range of column values. Must use! Example: Grade IN ('A','B','C','D','F') ...
... Useful for limiting the range of column values. Must use! Example: Grade IN ('A','B','C','D','F') ...
SQL
... can include up to 16 columns in an index, as long as the index doesn’t exceed the 900-byte limit. Both clustered and nonclustered indexes can be composite indexes. Unique Index: An index that ensures the uniqueness of each value in the indexed column. If the index is a composite, the uniqueness is ...
... can include up to 16 columns in an index, as long as the index doesn’t exceed the 900-byte limit. Both clustered and nonclustered indexes can be composite indexes. Unique Index: An index that ensures the uniqueness of each value in the indexed column. If the index is a composite, the uniqueness is ...
presentation source
... Finishing the Transaction • If the transaction goes successfully then the COMMIT command will commit the changes to the database. • However, if an error occurs the ROLLBACK command can be used to restore the database to its state prior to the transaction. ...
... Finishing the Transaction • If the transaction goes successfully then the COMMIT command will commit the changes to the database. • However, if an error occurs the ROLLBACK command can be used to restore the database to its state prior to the transaction. ...
Entity Relationship Diagram (ERD)
... Entities and Attributes • Entities and attributes define the columns of data in the database. • Entity- the subject of the table, i.e. “Vehicles.”. • Attributes- properties that describe the entity, i.e. “Mileage.” • Together, entities and attributes become tables organized by columns and rows. • E ...
... Entities and Attributes • Entities and attributes define the columns of data in the database. • Entity- the subject of the table, i.e. “Vehicles.”. • Attributes- properties that describe the entity, i.e. “Mileage.” • Together, entities and attributes become tables organized by columns and rows. • E ...
Document
... To connect accdb access file from a C# application you should download 2007 Office System Driver: Data Connectivity Components from the link below http://www.microsoft.com/en-us/download/details.aspx?id=23734 ...
... To connect accdb access file from a C# application you should download 2007 Office System Driver: Data Connectivity Components from the link below http://www.microsoft.com/en-us/download/details.aspx?id=23734 ...
Select?
... To connect accdb access file from a C# application you should download 2007 Office System Driver: Data Connectivity Components from the link below http://www.microsoft.com/en-us/download/details.aspx?id=23734 ...
... To connect accdb access file from a C# application you should download 2007 Office System Driver: Data Connectivity Components from the link below http://www.microsoft.com/en-us/download/details.aspx?id=23734 ...
Study Guide for Mid
... Derived attributes – what are they and what is the tradeoff that needs to be considered with respect to derived attributes? Existence dependence – give an example of two entities in which one entity is existence dependent on the other Strong and weak relationships / identifying and non-identifying r ...
... Derived attributes – what are they and what is the tradeoff that needs to be considered with respect to derived attributes? Existence dependence – give an example of two entities in which one entity is existence dependent on the other Strong and weak relationships / identifying and non-identifying r ...
Text 13 Database Management Systems
... The relational database is the most widely used database structure. Data is organized into related tables. Each table is made up of rows called records and columns called fields. Each record contains fields of data about some specific person, place, or thing. A DBMS provides a variety of tools to cr ...
... The relational database is the most widely used database structure. Data is organized into related tables. Each table is made up of rows called records and columns called fields. Each record contains fields of data about some specific person, place, or thing. A DBMS provides a variety of tools to cr ...
Data Warehouse performance and maintenance
... Data warehouse performance and maintenance Data warehousing has become an important technology even for small to mid-size companies for data analysis. One of the issues we encounter with data warehouses is performance, since we combine large amount of data from multiple data sources. ...
... Data warehouse performance and maintenance Data warehousing has become an important technology even for small to mid-size companies for data analysis. One of the issues we encounter with data warehouses is performance, since we combine large amount of data from multiple data sources. ...
DBCC CheckDB for Database Consistency
... DBCC CHECKDB is used to check the physical integrity of the entire database. DBCC CHECKDB is used to detect corruption in the database, and should be run regularly. This is accomplished by running several of the other DBCC commands, then doing some extra verification. Runs DBCC CHECKALLOC. Runs for ...
... DBCC CHECKDB is used to check the physical integrity of the entire database. DBCC CHECKDB is used to detect corruption in the database, and should be run regularly. This is accomplished by running several of the other DBCC commands, then doing some extra verification. Runs DBCC CHECKALLOC. Runs for ...
databases_mis
... relational database, the most prevalent. Relational database model stores information in the form of logically related two-dimensional tables. A relational database management system allows users to create, read, update, and delete data in a relational database. Entity (also referred to as a table) ...
... relational database, the most prevalent. Relational database model stores information in the form of logically related two-dimensional tables. A relational database management system allows users to create, read, update, and delete data in a relational database. Entity (also referred to as a table) ...
ProgressBook Suite Maintenance
... Shrinking Databases • Used to release large quantities of freed disk space • Pros: – Regain disk space from allocated ...
... Shrinking Databases • Used to release large quantities of freed disk space • Pros: – Regain disk space from allocated ...
Chap 6
... stored in adjacent memory locations and retrieved together as a unit Page: The amount of data read or written in one I/O operation Blocking Factor: The number of physical records per page ...
... stored in adjacent memory locations and retrieved together as a unit Page: The amount of data read or written in one I/O operation Blocking Factor: The number of physical records per page ...
Lec 1
... • Like the index in a book, they are tables that point to records, that can be read more quickly than scanning the whole book • They are usually B-trees • The key can be one attribute or made up of multiple attributes • There is usually one or more indexes for each table ...
... • Like the index in a book, they are tables that point to records, that can be read more quickly than scanning the whole book • They are usually B-trees • The key can be one attribute or made up of multiple attributes • There is usually one or more indexes for each table ...
Chapter 5 Updating Data
... The CHECK clause of the ALTER TABLE command is used to ensure that only legal values satisfying a particular condition are allowed in a given column If a user enters data that violates the condition, the DBMS rejects the update automatically ...
... The CHECK clause of the ALTER TABLE command is used to ensure that only legal values satisfying a particular condition are allowed in a given column If a user enters data that violates the condition, the DBMS rejects the update automatically ...