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  2. MapInfo TAB format - Wikipedia

    en.wikipedia.org/wiki/MapInfo_TAB_format

    Normal temporary files have the following file name extensions: .TDA Temporary database file.TIN Temporary index file.TMA Temporary Map File; When using a database table such as Oracle Locator or Spatial, if the data is downloaded to the local machine, the temporary file name extensions are: .LDA Local Temporary database file

  3. Oracle Database - Wikipedia

    en.wikipedia.org/wiki/Oracle_Database

    Oracle Database (commonly referred to as Oracle DBMS, Oracle Autonomous Database, or simply as Oracle) is a proprietary multi-model [4] database management system produced and marketed by Oracle Corporation. It is a database commonly used for running online transaction processing (OLTP), data warehousing (DW) and mixed (OLTP & DW) database ...

  4. SQL syntax - Wikipedia

    en.wikipedia.org/wiki/SQL_syntax

    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.

  5. Hierarchical and recursive queries in SQL - Wikipedia

    en.wikipedia.org/wiki/Hierarchical_and_recursive...

    A common table expression, or CTE, (in SQL) is a temporary named result set, derived from a simple query and defined within the execution scope of a SELECT, INSERT, UPDATE, or DELETE statement. CTEs can be thought of as alternatives to derived tables ( subquery ), views , and inline user-defined functions.

  6. Database index - Wikipedia

    en.wikipedia.org/wiki/Database_index

    A database index is a data structure that improves the speed of data retrieval operations on a database table at the cost of additional writes and storage space to maintain the index data structure. Indexes are used to quickly locate data without having to search every row in a database table every time said table is accessed.

  7. Materialized view - Wikipedia

    en.wikipedia.org/wiki/Materialized_view

    Materialized views that store data based on remote tables were also known as snapshots [5] (deprecated Oracle terminology). In any database management system following the relational model, a view is a virtual table representing the result of a database query. Whenever a query or an update addresses an ordinary view's virtual table, the DBMS ...

  8. Bitmap index - Wikipedia

    en.wikipedia.org/wiki/Bitmap_index

    Applying this access strategy to B-tree indexes can also combine range queries on multiple columns. In this approach, a temporary in-memory bitmap is created with one bit for each row in the table (1 MB can thus store over 8 million entries). Next, the results from each index are combined into the bitmap using bitwise operations. After all ...

  9. Data dictionary - Wikipedia

    en.wikipedia.org/wiki/Data_dictionary

    Oracle has a list of specific views for the "sys" user. This allows users to look up the exact information that is needed. Command files contain SQL Statements for CREATE TABLE, CREATE UNIQUE INDEX, ALTER TABLE (for referential integrity), etc., using the specific statement required by that type of database.