Terminology: SQL versus traditional file access
DB2® for IBM® i provides two access methods for manipulating database tables and data: SQL and system file access methods. These access methods use different words to describe some similar concepts.
SQL term | Traditional file access term |
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Schema. A group of related objects that consists of a library, a journal, a journal receiver, an SQL catalog, and an optional data dictionary. A schema enables the user to find the objects by name. Another name for a schema is collection. | Library. A group of related objects that enables the user to find the objects by name. |
Table. A set of columns and rows. | Physical file. A set of records. |
Row. The horizontal part of a table containing a serial set of columns. | Record. A set of fields. |
Column. The vertical part of a table of one data type. | Field. One of more bytes of related information of one data type. |
View. A subset of columns and rows of one or more tables. | Logical file. A subset of fields or records of up to 32 physical files. |
Index. A collection of data in the columns of a table, logically arranged in ascending or descending order. | Index. A type of logical file. |
Package. An object that contains control structures for SQL statements to be used by an application server. | SQL package. An object that contains control structures for SQL statements to be used by an application server. |
Catalog. A set of tables and views that contain information about tables, packages, views, indexes, and constraints. | No similar object. However, the Display File Description (DSPFD) and Display File Field Description (DSPFFD) commands provide some of the same information that querying an SQL catalog provides. |