Database_performance
... separating the indexes from the data • Consider separating the indexes from the data, if possible. Database queries are frequently required to access data from both the table and an index on that table. If both of these files reside on the same disk device, performance degradation is likely. • To r ...
... separating the indexes from the data • Consider separating the indexes from the data, if possible. Database queries are frequently required to access data from both the table and an index on that table. If both of these files reside on the same disk device, performance degradation is likely. • To r ...
SQL Wildcards
... Using the COUNT aggregate function to find totals The COUNT(column_name) function returns the number of values (NULL values will not be counted) of the specified column: SELECT COUNT(*) FROM ORDER_LINE_V WHERE ORDER_ID = 1004; ...
... Using the COUNT aggregate function to find totals The COUNT(column_name) function returns the number of values (NULL values will not be counted) of the specified column: SELECT COUNT(*) FROM ORDER_LINE_V WHERE ORDER_ID = 1004; ...
2440: 180 Database Concepts - gozips.uakron.edu
... • User unaware of behind the scenes replication of the data ...
... • User unaware of behind the scenes replication of the data ...
Access Unit 1 Exam
... 6. In Access 2007, you can view a datasheet and a form _______. a. independently b. for set time periods c. simultaneously d. none of the above 7. _______ are the details about a file. a. Database properties b. Database objects c. Database certificates d. none of the above 8. A collection of organiz ...
... 6. In Access 2007, you can view a datasheet and a form _______. a. independently b. for set time periods c. simultaneously d. none of the above 7. _______ are the details about a file. a. Database properties b. Database objects c. Database certificates d. none of the above 8. A collection of organiz ...
Introduction - Homepages | The University of Aberdeen
... • Data to be structured, defined and stored independent of application programs – Data + metadata = database (another definition!) ...
... • Data to be structured, defined and stored independent of application programs – Data + metadata = database (another definition!) ...
PPT - Open Access Repository
... keeping in mind that standards solve cross database communication issues. as an example, many programmers take for granted that the DBSM keeps an internal ID for a table (useful to join tables together). This is NOT an SQL standard: porting data to another DBMS becomes suddenly a nightmare. This f ...
... keeping in mind that standards solve cross database communication issues. as an example, many programmers take for granted that the DBSM keeps an internal ID for a table (useful to join tables together). This is NOT an SQL standard: porting data to another DBMS becomes suddenly a nightmare. This f ...
DATABASE ADMINISTRATORS
... Administer, test, and implement computer databases, applying knowledge of database management systems. Coordinate changes to computer databases. May plan, coordinate, and implement security measures to safeguard computer databases. •Manage technical projects including involvement from local and glob ...
... Administer, test, and implement computer databases, applying knowledge of database management systems. Coordinate changes to computer databases. May plan, coordinate, and implement security measures to safeguard computer databases. •Manage technical projects including involvement from local and glob ...
Introduction to Oracle - University of Windsor
... block buffer cache and dictionary cache. DBWR performs batch writes of changed block. Since Oracle uses write-ahead logging, DBWR does not need to write blocks when a transaction commits. In the most common case, DBWR writes only when more data needs to be read into the system global area and too fe ...
... block buffer cache and dictionary cache. DBWR performs batch writes of changed block. Since Oracle uses write-ahead logging, DBWR does not need to write blocks when a transaction commits. In the most common case, DBWR writes only when more data needs to be read into the system global area and too fe ...
SQL Server and SQL
... • If the table name is “COURSE”, name the Primary Key column “CourseId”, etc. • “Always” use Integer and Identity(1,1) for Primary Keys. Use UNIQUE constraint for other columns that needs to be unique, e.g. “RoomNumber” • Specify Required Columns (NOT NULL) – i.e., which columns that need to hav ...
... • If the table name is “COURSE”, name the Primary Key column “CourseId”, etc. • “Always” use Integer and Identity(1,1) for Primary Keys. Use UNIQUE constraint for other columns that needs to be unique, e.g. “RoomNumber” • Specify Required Columns (NOT NULL) – i.e., which columns that need to hav ...
Proceedings of the 1st Conference on Network Administration Network Documentation:
... relational databases at the back end to store and organize this information. We envision that this Webbased system will be used in an intranet environment and will provide several levels of access to di erent user types. ...
... relational databases at the back end to store and organize this information. We envision that this Webbased system will be used in an intranet environment and will provide several levels of access to di erent user types. ...
ReadMe document
... transform? Yes, it would, but not all that much more efficient. In this case, we valued the documentation benefits of dividing the work, more than the modest performance gain by combining all into a single transform. o The other complexity in the Product package is the historical reconstruction of t ...
... transform? Yes, it would, but not all that much more efficient. In this case, we valued the documentation benefits of dividing the work, more than the modest performance gain by combining all into a single transform. o The other complexity in the Product package is the historical reconstruction of t ...
Understanding Transactions
... Available for all Firebird isolation levels. Tables are reserved for the specified access when the transaction is started (prevent possible deadlocks and update conflicts that can occur if locks are taken only ...
... Available for all Firebird isolation levels. Tables are reserved for the specified access when the transaction is started (prevent possible deadlocks and update conflicts that can occur if locks are taken only ...
CIS 8040 – Fundamentals of Database Management Systems
... Class sessions will comprise (1) lecture/discussion of certain database software concepts and features, (2) instructor demonstrations of these same database software concepts and features, and (3) student lab sessions working with these same database software concepts and features. The purpose of th ...
... Class sessions will comprise (1) lecture/discussion of certain database software concepts and features, (2) instructor demonstrations of these same database software concepts and features, and (3) student lab sessions working with these same database software concepts and features. The purpose of th ...
driver
... • In SQL, NULL means the field is empty • Not the same as 0 or “” • In JDBC, you must explicitly ask if a field is null by calling ResultSet.isNull(column) ...
... • In SQL, NULL means the field is empty • Not the same as 0 or “” • In JDBC, you must explicitly ask if a field is null by calling ResultSet.isNull(column) ...
Exam 1
... Fill in the blanks to accurately describe the connection of, and activities at, each level. [8 pts] Entity-relationship modeling is at the ____________ level. Conversion of the ER model to the relational model is found at the ________________ level. Specifying relationships and their cardinality occ ...
... Fill in the blanks to accurately describe the connection of, and activities at, each level. [8 pts] Entity-relationship modeling is at the ____________ level. Conversion of the ER model to the relational model is found at the ________________ level. Specifying relationships and their cardinality occ ...
marked - Kansas State University
... Indices offer substantial benefits when searching for records. When a file is modified, every index on the file must be updated, Updating indices imposes overhead on database modification. Sequential scan using primary index is efficient, but a sequential scan using a secondary index is expens ...
... Indices offer substantial benefits when searching for records. When a file is modified, every index on the file must be updated, Updating indices imposes overhead on database modification. Sequential scan using primary index is efficient, but a sequential scan using a secondary index is expens ...
Introduction to SQL Tuning - Department of Computer and
... – “I’m not a SQL programmer, I’m a ... VB/PowerBuilder/C++/Java programmer.” – “I’ll write the SQL, someone else (DBA) can tune it for me later.” – “I’ll tune it later” – “We can’t afford to tune it” ...
... – “I’m not a SQL programmer, I’m a ... VB/PowerBuilder/C++/Java programmer.” – “I’ll write the SQL, someone else (DBA) can tune it for me later.” – “I’ll tune it later” – “We can’t afford to tune it” ...
Final Exam Database Processing
... ____ 13. During the initial stages of the implementation phase, the system enters into a cycle of coding, testing, and debugging. ____ 14. Database performance is one of the most important factors in certain database implementations. ____ 15. To ensure consistency of the database, every transaction ...
... ____ 13. During the initial stages of the implementation phase, the system enters into a cycle of coding, testing, and debugging. ____ 14. Database performance is one of the most important factors in certain database implementations. ____ 15. To ensure consistency of the database, every transaction ...
Oracle Database 11g - Greater Cincinnati Oracle Users Group
... • One consistent way to manage all your data • Not just for data warehouse and high-end OLTP any more • New referential, virtual column, composite, and interval partitioning features bring partitioning to mainstream • Easier management of today’s rapidly growing datasets • Improved performance • Par ...
... • One consistent way to manage all your data • Not just for data warehouse and high-end OLTP any more • New referential, virtual column, composite, and interval partitioning features bring partitioning to mainstream • Easier management of today’s rapidly growing datasets • Improved performance • Par ...
DATA MODELS
... All operations are performed on an entire relation and result is an entire relation, a concept known as closure. ...
... All operations are performed on an entire relation and result is an entire relation, a concept known as closure. ...