| sql | FidoNet Squish Lastread Storage |
| sql | SQL Script |
| sqlite | SQLite Database |
| sqlite-shm | SQLite Shared Memory Data |
| sqlite-wal | SQLite Quasi-persistent Data |
| sqlite2 | SQLite 2.0 Database |
| sqlite3 | SQLite 3 Database |
| sqlitedb | SQLite Database |
| sqlitedb-shm | SQLite Shared Memory Data |
| sqlitedb-wal | SQLite Quasi-persistent Data |
| sqlplan | Microsoft SQL Server Database Plan |
| sqlt | SQLite Database |
| sqlx | JAX-DB SQLx Data |
| sqm | Microsoft Message Queuing Data |
| sqp | Sonique Audio Search Query Result Data |
| sqs | SQL Script Sequences |
| squ | LabWindows Test Sequence |
| sqv | VisionWorks LS Image Sequence Data |
| sqw | Horace Data |
| sqy | Xaira Saved Query |
| sr1 | SIR Schema Rectype and Variable Specs Data |
| sr2 | SIR Schema Textual Specs Data |
| sr3 | SIR Index and Data |
| sr4 | SIR Procedure Definitions Data |
| sr5 | SIR Database Journal Data |
| sr6 | SIR Alternate Index |
| sr7 | SAS Item Storage |
| sr8 | RECOIL Data |
| sra | Sequence Read Archive |
| src | AQUA Disulphide Distance Restraints Counts Data |
| srd | Smart Reminder Database |
| srd | Summary Record Database |
| srec | Motorola S-record Data |
| srf | BrainVoyager QX Surface Data |
| srf | Lightwave 3D Surface Data |
