pub struct ReservedBytesPerPage(_);Expand description
SQLite has the ability to set aside a small number of extra bytes at the end of every page for use by extensions. These extra bytes are used, for example, by the SQLite Encryption Extension to store a nonce and/or cryptographic checksum associated with each page. The “reserved space” size in the 1-byte integer at offset 20 is the number of bytes of space at the end of each page to reserve for extensions. This value is usually 0. The value can be odd.
The “usable size” of a database page is the page size specified by the
2-byte integer at offset 16 in the header less the “reserved” space size
recorded in the 1-byte integer at offset 20 in the header. The usable size
of a page might be an odd number. However, the usable size is not allowed
to be less than 480. In other words, if the page size is 512, then the
reserved space size cannot exceed 32.