Classes para Manipulação de BDs 5
... Known as “recordsets,” CRecordset objects are typically used in two forms: dynasets and snapshots. A dynaset stays synchronized with data updates made by other users. A snapshot is a static view of the data. Each form represents a set of records fixed at the time the recordset is opened, but when yo ...
... Known as “recordsets,” CRecordset objects are typically used in two forms: dynasets and snapshots. A dynaset stays synchronized with data updates made by other users. A snapshot is a static view of the data. Each form represents a set of records fixed at the time the recordset is opened, but when yo ...
SORT_CALCULATE PPt - University of Arkansas
... by combining columns, also known as concatenated columns. /* Combine 2 columns into one (concatenate columns). ...
... by combining columns, also known as concatenated columns. /* Combine 2 columns into one (concatenate columns). ...
Transaction Management Overview
... A transaction might commit after completing all its actions, or it could abort (or be aborted by the DBMS) after executing some actions. A very important property guaranteed by the DBMS for all transactions is that they are atomic. That is, a user can think of a Xact as always executing all its ac ...
... A transaction might commit after completing all its actions, or it could abort (or be aborted by the DBMS) after executing some actions. A very important property guaranteed by the DBMS for all transactions is that they are atomic. That is, a user can think of a Xact as always executing all its ac ...
Chapter 11
... – Crucial in speeding up data access – Facilitate searching, sorting, and using aggregate functions as well as join operations – Ordered set of values that contains index key and pointers ...
... – Crucial in speeding up data access – Facilitate searching, sorting, and using aggregate functions as well as join operations – Ordered set of values that contains index key and pointers ...
SQL
... The SELECT clause is used to query (search) the database It SELECTS the records matching the criteria you specify ...
... The SELECT clause is used to query (search) the database It SELECTS the records matching the criteria you specify ...
Sample Chapter 4 Data Buffering - dFPUG
... Row Buffering is used sometimes temporarily, for instance to add indexes to a buffered table or view, you must NOT have table buffering on. Table Buffering is what you will really use most of the time in your apps. None of the users changes is saved until you explicitly save them with TABLEUPDATE() ...
... Row Buffering is used sometimes temporarily, for instance to add indexes to a buffered table or view, you must NOT have table buffering on. Table Buffering is what you will really use most of the time in your apps. None of the users changes is saved until you explicitly save them with TABLEUPDATE() ...
Physical Database Design II
... Physical Database Design and Database Tuning, R. Ramakrishnan and J. Gehrke, modified by Ch. Eick ...
... Physical Database Design and Database Tuning, R. Ramakrishnan and J. Gehrke, modified by Ch. Eick ...
An Interface Between the SAS System and the INFORMIX Database
... error was high and reproducibility was difficult. Additionally, because the database tools being used were not primarily designed for the mathematical data manipulations required, the programming was more difficult and very labour intensive. This system was not satisfactory, and a better method of d ...
... error was high and reproducibility was difficult. Additionally, because the database tools being used were not primarily designed for the mathematical data manipulations required, the programming was more difficult and very labour intensive. This system was not satisfactory, and a better method of d ...
DATABASE ADMINISTRATOR I -
... ABCWUA Position Description DATABASE ADMINISTRATOR I Status APPROVED ...
... ABCWUA Position Description DATABASE ADMINISTRATOR I Status APPROVED ...
4/3 Physical Database Design
... RAID-3 - single-user only RAID-5 - higher speed than single disk, fault tolerant, multi-user, but some storage cost and slower write times ...
... RAID-3 - single-user only RAID-5 - higher speed than single disk, fault tolerant, multi-user, but some storage cost and slower write times ...
lecture7
... connected and arrange your data into simple two-dimensional, unordered tables, then you can develop an algebra for queries and focus on the data as data, not as a physical realization of a logical model” ...
... connected and arrange your data into simple two-dimensional, unordered tables, then you can develop an algebra for queries and focus on the data as data, not as a physical realization of a logical model” ...
CS186: Introduction to Database Systems
... – Before a change is made to the database, the corresponding log entry is forced to a safe location. (WAL protocol; OS support for this is often inadequate.) – After a crash, the effects of partially executed transactions are undone using the log. Effects of committed transactions are redone using t ...
... – Before a change is made to the database, the corresponding log entry is forced to a safe location. (WAL protocol; OS support for this is often inadequate.) – After a crash, the effects of partially executed transactions are undone using the log. Effects of committed transactions are redone using t ...
File Systems and Databases - Department of Computer Science
... Data dependence makes file systems extremely cumbersome from a programming and data management point of view. ...
... Data dependence makes file systems extremely cumbersome from a programming and data management point of view. ...
- EdShare
... • Flat transaction - one ACID unit which locks all records for the duration • Chained transaction - one record locked at a time, so other updates can occur during the run ...
... • Flat transaction - one ACID unit which locks all records for the duration • Chained transaction - one record locked at a time, so other updates can occur during the run ...
The Relational Data Model
... that is, AGENT_CODE—occurs only once in the new table • If the same AGENT_CODE were to occur several times in the AGENT table, – a customer would be listed for each match ...
... that is, AGENT_CODE—occurs only once in the new table • If the same AGENT_CODE were to occur several times in the AGENT table, – a customer would be listed for each match ...
Introduction to Database Systems
... (Strict 2PL locking protocol.) Idea: If an action of Ti (say, writing X) affects Tj (which perhaps reads X), one of them, say Ti, will obtain the lock on X first and Tj is forced to wait until Ti completes; this effectively orders the transactions. What if Tj already has a lock on Y and Ti later req ...
... (Strict 2PL locking protocol.) Idea: If an action of Ti (say, writing X) affects Tj (which perhaps reads X), one of them, say Ti, will obtain the lock on X first and Tj is forced to wait until Ti completes; this effectively orders the transactions. What if Tj already has a lock on Y and Ti later req ...
Phase 3. Systems Design
... – Candidate key – any field(s) that could be primary key • Nonkey field – not primary or candidate ...
... – Candidate key – any field(s) that could be primary key • Nonkey field – not primary or candidate ...
Moving the SQL Monitor database
... 1. Stop the Base Monitor service. To do this, go to Services (select Start > Run, enter services.msc and click OK) and stop SQL Monitor 4 Base Monitor. 2. In your SQL Server management tool, back up your current Data Repository database and then restore it to your preferred location. If you did not ...
... 1. Stop the Base Monitor service. To do this, go to Services (select Start > Run, enter services.msc and click OK) and stop SQL Monitor 4 Base Monitor. 2. In your SQL Server management tool, back up your current Data Repository database and then restore it to your preferred location. If you did not ...
ppt - EECS Instructional Support Group Home Page
... To do their job, database systems exhibit the following properties: • Atomicity – database operations either execute, or they don’t, they never stop in the middle. • Consistency – an operation never leaves the database in an inconsistent state • Isolation – multiple users can operate on a database w ...
... To do their job, database systems exhibit the following properties: • Atomicity – database operations either execute, or they don’t, they never stop in the middle. • Consistency – an operation never leaves the database in an inconsistent state • Isolation – multiple users can operate on a database w ...
Database Administration Presentation
... Imagine that the current database is inaccurate. This database must be replaced with a prior, consistent version of the database before forward recovery can begin. After-images are applied to a past version of the database. Does not require that all transactions are applied - just takes the most ...
... Imagine that the current database is inaccurate. This database must be replaced with a prior, consistent version of the database before forward recovery can begin. After-images are applied to a past version of the database. Does not require that all transactions are applied - just takes the most ...
Course Information and Introduction to Data Management
... from B’s account to A’s account. The second is crediting both accounts with a 6% interest payment. There is no guarantee that T1 will execute before T2 or vice-versa, if both are submitted together. However, the net effect must be equivalent to these two transactions running serially in some order ...
... from B’s account to A’s account. The second is crediting both accounts with a 6% interest payment. There is no guarantee that T1 will execute before T2 or vice-versa, if both are submitted together. However, the net effect must be equivalent to these two transactions running serially in some order ...
Database & Data Warehouse
... Information Cleansing or Scrubbing Organizations must maintain high-quality data in the data warehouse Information cleansing or scrubbing – a process that weeds out and fixes or discards inconsistent, incorrect, or incomplete information – first, occurs during ETL. Then, when the data is in the D ...
... Information Cleansing or Scrubbing Organizations must maintain high-quality data in the data warehouse Information cleansing or scrubbing – a process that weeds out and fixes or discards inconsistent, incorrect, or incomplete information – first, occurs during ETL. Then, when the data is in the D ...
