| data | Analysis Studio Data |
| data | General Data File |
| database | Serato DJ Database |
| datbak0 | Miranda IM Data Backup |
| datd | Daily Aggregated Traffic Data |
| datr | DATR Data |
| datt | STK Processed Intermediate Terrain File |
| datx | Canon EOS Utility Data |
| dau | SPSS Overflow Data |
| dawn | DAWN Science Data |
| day | WRAP DAY Output Data |
| da_ | Compressed DAT File |
| da_ | GKSetup Support Data |
| db | General Database File |
| db | Skype Chat History Data |
| db$ | dBase Temporary Data |
| db- | Norton Utilities Nprotect Database |
| db-journal | SQLite Rollback Journal Data |
| db-shm | SQLite Database Shared Memory |
| db-wal | SQLite Database Write-Ahead Log |
| db1 | Tekla Structures Model |
| db2 | dBASE II Database |
| db2 | Tekla Numbering Database |
| db2ind | Microsoft Visual Studio DB2 Index Data |
| db3 | Berkeley DB3 Database |
| db3-wal | SQLite 3 Write-Ahead Log |
| db4 | dBASE IV Database |
| dba | Gridgen Geometry Data |
| dba | Steinberg WaveLab Audio Database |
| dban | DBAN Data |
| dbas | AQUA Database |
| dbat | Intuit Quicken for Mac DBAT Data |
| dbb | Skype Binary Log File |
| dbc | DAZ Studio Brick Camera |
| dbc | Microsoft Visual FoxPro Database |
