In Structured Query Language (SQL), theWHEREclause is used to filter records based on specified criteria. The query retrievesall columnsfrom thepatienttable (SELECT *) but onlythose rowswhere themedical_record_numbervalue is greater than 9000.
This means:
Thenumber of columns (fields)remains the same as the original table.
Thenumber of rows (records)will beequal to or less thanthe number of rows in thepatienttable, depending on how many patients meet the filter condition.
Hence, the result set can only beshorter or equal in lengthcompared to the original table. It cannot be longer, wider, or narrower, since no new rows or columns are created.
Therefore,option B—“Shorter or of equal length than the patient table”— is correct.
Reference (CCDM-Verified Sources):
SCDM GCDMP, Chapter: Database Design and Build, Section 5.2 – Relational Database Queries and Filtering Logic
ICH E6(R2) GCP, Section 5.5.3 – Data Retrieval, Filtering, and Storage Principles
FDA Guidance for Industry: Computerized Systems Used in Clinical Investigations, Section 6.4 – Query Logic and Record Subsetting