


How to Fetch Specific Column Names from an Oracle Table, Excluding Certain Columns?
Oracle query to extract column names
Question:
Modify a MySQL query to extract column names from a table in an Oracle 11g database, specifically excluding certain columns and specifying a schema. It's not clear whether it is possible to use the tablespace name instead of the schema name.
Solution:
1. Oracle equivalent of MySQL query:
The Oracle equivalent of MySQL's information_schema.COLUMNS is USER_TAB_COLS (for tables owned by the current user), or ALL_TAB_COLS or DBA_TAB_COLS (for tables owned by all users).
2. Schema and table space:
Tablespace is not equivalent to schema. Tablespace refers to the physical storage of database objects, while schema refers to the logical grouping of database objects.
3. Oracle query example:
This is a modified Oracle query to extract column names from the users table, excluding specified columns and specifying the schema:
SELECT column_name FROM all_tab_cols WHERE table_name = 'USERS' AND owner = '[_db]' AND column_name NOT IN ('PASSWORD', 'VERSION', 'ID')
Note:
- As shown in the query, Oracle table and column names are usually stored in uppercase.
- Be sure to prevent SQL injection when providing user input in queries.
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