1.Dd January 24, 2024 2.Dt SQLITE3_SNAPSHOT 3 3.Os 4.Sh NAME 5.Nm sqlite3_snapshot 6.Nd database snapshot 7.Sh SYNOPSIS 8.In sqlite3.h 9.Vt typedef struct sqlite3_snapshot { unsigned char hidden[48]; } sqlite3_snapshot; 10.Sh DESCRIPTION 11An instance of the snapshot object records the state of a WAL mode 12database for some specific point in history. 13.Pp 14In WAL mode, multiple database connections 15that are open on the same database file can each be reading a different 16historical version of the database file. 17When a database connection begins a read transaction, 18that connection sees an unchanging copy of the database as it existed 19for the point in time when the transaction first started. 20Subsequent changes to the database from other connections are not seen 21by the reader until a new read transaction is started. 22.Pp 23The sqlite3_snapshot object records state information about an historical 24version of the database file so that it is possible to later open a 25new read transaction that sees that historical version of the database 26rather than the most recent version. 27.Sh IMPLEMENTATION NOTES 28These declarations were extracted from the 29interface documentation at line 10446. 30.Bd -literal 31typedef struct sqlite3_snapshot { 32 unsigned char hidden[48]; 33} sqlite3_snapshot; 34.Ed 35.Sh SEE ALSO 36.Xr sqlite3 3 37