SQL administration (storage management): which SQL command is used to allocate an extent for an existing table (for example, to grow its on-disk storage)?

Introduction / Context: Some SQL dialects, especially those influenced by Oracle-style storage management, expose commands to influence physical storage, such as allocating additional extents to a segment. Although modern systems often auto-extend, administrators may still manually allocate space for performance or maintenance reasons.

Given Data / Assumptions:

• We are dealing with an already existing table.
• The task is “allocate an extent,” i.e., reserve additional contiguous storage for the table segment.
• We seek the correct DDL verb used by mainstream SQL systems that support this feature.

Concept / Approach: The command to change attributes or storage for an existing table is ALTER TABLE. In engines that support manual extent control, administrators issue statements like “ALTER TABLE table_name ALLOCATE EXTENT” with optional storage parameters. Pseudo-commands such as “MODIFY ALLOCATES,” “MODIFY TABLE,” or “REDEFINE TABLE” are not standard SQL DDL forms.

Step-by-Step Solution:

Verification / Alternative check: Storage clauses and extent management appear in vendor documentation with the ALTER TABLE command family, not with nonstandard verbs like “MODIFY TABLE.”

Why Other Options Are Wrong:

Common Pitfalls: Confusing logical schema DDL (columns, constraints) with physical storage options; or assuming every RDBMS exposes extent-level control—many manage extents automatically.

Final Answer: ALTER TABLE