SQLITE_DBSTATUS_LOOKASIDE_USED
,
SQLITE_DBSTATUS_CACHE_USED
,
SQLITE_DBSTATUS_SCHEMA_USED
,
SQLITE_DBSTATUS_STMT_USED
,
SQLITE_DBSTATUS_LOOKASIDE_HIT
,
SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
,
SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
,
SQLITE_DBSTATUS_CACHE_HIT
,
SQLITE_DBSTATUS_CACHE_MISS
,
SQLITE_DBSTATUS_CACHE_WRITE
,
SQLITE_DBSTATUS_DEFERRED_FKS
,
SQLITE_DBSTATUS_CACHE_USED_SHARED
,
SQLITE_DBSTATUS_CACHE_SPILL
,
SQLITE_DBSTATUS_MAX
—
Status Parameters for database connections
#define SQLITE_DBSTATUS_LOOKASIDE_USED
#define SQLITE_DBSTATUS_CACHE_USED
#define SQLITE_DBSTATUS_SCHEMA_USED
#define SQLITE_DBSTATUS_STMT_USED
#define SQLITE_DBSTATUS_LOOKASIDE_HIT
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
#define SQLITE_DBSTATUS_CACHE_HIT
#define SQLITE_DBSTATUS_CACHE_MISS
#define SQLITE_DBSTATUS_CACHE_WRITE
#define SQLITE_DBSTATUS_DEFERRED_FKS
#define SQLITE_DBSTATUS_CACHE_USED_SHARED
#define SQLITE_DBSTATUS_CACHE_SPILL
#define SQLITE_DBSTATUS_MAX
These constants are the available integer "verbs" that can be passed
as the second argument to the sqlite3_db_status() interface.
New verbs may be added in future releases of SQLite. Existing
verbs might be discontinued. Applications should check the return code from
sqlite3_db_status() to make sure that the call worked. The
sqlite3_db_status() interface will return a non-zero error code if a
discontinued or unsupported verb is invoked.
- SQLITE_DBSTATUS_LOOKASIDE_USED
- This parameter returns the number of lookaside memory slots currently
checked out.
- SQLITE_DBSTATUS_LOOKASIDE_HIT
- This parameter returns the number malloc attempts that were satisfied
using lookaside memory. Only the high-water value is meaningful; the
current value is always zero.
- SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
- This parameter returns the number malloc attempts that might have been
satisfied using lookaside memory but failed due to the amount of memory
requested being larger than the lookaside slot size. Only the high-water
value is meaningful; the current value is always zero.
- SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
- This parameter returns the number malloc attempts that might have been
satisfied using lookaside memory but failed due to all lookaside memory
already being in use. Only the high-water value is meaningful; the current
value is always zero.
- SQLITE_DBSTATUS_CACHE_USED
- This parameter returns the approximate number of bytes of heap memory used
by all pager caches associated with the database connection. The highwater
mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
- SQLITE_DBSTATUS_CACHE_USED_SHARED
- This parameter is similar to DBSTATUS_CACHE_USED, except that if a pager
cache is shared between two or more connections the bytes of heap memory
used by that pager cache is divided evenly between the attached
connections. In other words, if none of the pager caches associated with
the database connection are shared, this request returns the same value as
DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are shared,
the value returned by this call will be smaller than that returned by
DBSTATUS_CACHE_USED. The highwater mark associated with
SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
- SQLITE_DBSTATUS_SCHEMA_USED
- This parameter returns the approximate number of bytes of heap memory used
to store the schema for all databases associated with the connection -
main, temp, and any ATTACH-ed databases. The full amount of memory used by
the schemas is reported, even if the schema memory is shared with other
database connections due to shared cache mode being enabled. The highwater
mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
- SQLITE_DBSTATUS_STMT_USED
- This parameter returns the approximate number of bytes of heap and
lookaside memory used by all prepared statements associated with the
database connection. The highwater mark associated with
SQLITE_DBSTATUS_STMT_USED is always 0.
- SQLITE_DBSTATUS_CACHE_HIT
- This parameter returns the number of pager cache hits that have occurred.
The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT is always
0.
- SQLITE_DBSTATUS_CACHE_MISS
- This parameter returns the number of pager cache misses that have
occurred. The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS is
always 0.
- SQLITE_DBSTATUS_CACHE_WRITE
- This parameter returns the number of dirty cache entries that have been
written to disk. Specifically, the number of pages written to the wal file
in wal mode databases, or the number of pages written to the database file
in rollback mode databases. Any pages written as part of transaction
rollback or database recovery operations are not included. If an IO or
other error occurs while writing a page to disk, the effect on subsequent
SQLITE_DBSTATUS_CACHE_WRITE requests is undefined. The highwater mark
associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
- SQLITE_DBSTATUS_CACHE_SPILL
- This parameter returns the number of dirty cache entries that have been
written to disk in the middle of a transaction due to the page cache
overflowing. Transactions are more efficient if they are written to disk
all at once. When pages spill mid-transaction, that introduces additional
overhead. This parameter can be used help identify inefficiencies that can
be resolve by increasing the cache size.
- SQLITE_DBSTATUS_DEFERRED_FKS
- This parameter returns zero for the current value if and only if all
foreign key constraints (deferred or immediate) have been resolved. The
highwater mark is always 0.