Search results
Results from the WOW.Com Content Network
A database dump contains a record of the table structure and/or the data from a database and is usually in the form of a list of SQL statements ("SQL dump"). A database dump is most often used for backing up a database so that its contents can be restored in the event of data loss.
versatile data structure – sequential as well as random access; access is fast; supports exact, range, part key and pattern matches efficiently. volatile files are handled efficiently because index is dynamic – expands and contracts as table grows and shrinks; less well suited to relatively stable files – in this case, ISAM is more efficient
Through the use of standby redo log files, Data Guard can minimize data loss. [ 15 ] It supports heterogeneous configurations in which the primary and standby systems may have different CPU architectures, operating systems (for example, Microsoft Windows and Linux), operating-system binaries (32-bit/64-bit), or Oracle database binaries (32-bit ...
Most relational database designs resolve many-to-many relationships by creating an additional table that contains the PKs from both of the other entity tables – the relationship becomes an entity; the resolution table is then named appropriately and the two FKs are combined to form a PK. The migration of PKs to other tables is the second ...
The term "schema" refers to the organization of data as a blueprint of how the database is constructed (divided into database tables in the case of relational databases). The formal definition of a database schema is a set of formulas (sentences) called integrity constraints imposed on a database.
It uses the MySQL client library API as a data transport, treating remote tables as if they were located on the local server. Each Federated table that is defined there is one .frm (data definition file containing information such as the URL of the data source). The actual data can exist on a local or remote MySQL instance.
A derived table is the use of referencing an SQL subquery in a FROM clause. Essentially, the derived table is a subquery that can be selected from or joined to. The derived table functionality allows the user to reference the subquery as a table. The derived table is sometimes referred to as an inline view or a subselect.
With them we can easily allow or deny some actions for users on the tables or records (row level security). DCL commands are: [2] GRANT gives specified permissions for the table (and other objects) to, or assigns a specified role with certain permissions to, specified groups or users of a database; REVOKE