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Elixir Cross Referencer

.Dd December 19, 2018
.Dt SQLITE_STMTSTATUS_FULLSCAN_STEP 3
.Os
.Sh NAME
.Nm SQLITE_STMTSTATUS_FULLSCAN_STEP ,
.Nm SQLITE_STMTSTATUS_SORT ,
.Nm SQLITE_STMTSTATUS_AUTOINDEX ,
.Nm SQLITE_STMTSTATUS_VM_STEP ,
.Nm SQLITE_STMTSTATUS_REPREPARE ,
.Nm SQLITE_STMTSTATUS_RUN ,
.Nm SQLITE_STMTSTATUS_MEMUSED
.Nd Status Parameters for prepared statements
.Sh SYNOPSIS
.Fd #define SQLITE_STMTSTATUS_FULLSCAN_STEP
.Fd #define SQLITE_STMTSTATUS_SORT
.Fd #define SQLITE_STMTSTATUS_AUTOINDEX
.Fd #define SQLITE_STMTSTATUS_VM_STEP
.Fd #define SQLITE_STMTSTATUS_REPREPARE
.Fd #define SQLITE_STMTSTATUS_RUN
.Fd #define SQLITE_STMTSTATUS_MEMUSED
.Sh DESCRIPTION
These preprocessor macros define integer codes that name counter values
associated with the sqlite3_stmt_status() interface.
The meanings of the various counters are as follows: 
.Bl -tag -width Ds
.It SQLITE_STMTSTATUS_FULLSCAN_STEP
This is the number of times that SQLite has stepped forward in a table
as part of a full table scan.
Large numbers for this counter may indicate opportunities for performance
improvement through careful use of indices.
.It SQLITE_STMTSTATUS_SORT
This is the number of sort operations that have occurred.
A non-zero value in this counter may indicate an opportunity to improvement
performance through careful use of indices.
.It SQLITE_STMTSTATUS_AUTOINDEX
This is the number of rows inserted into transient indices that were
created automatically in order to help joins run faster.
A non-zero value in this counter may indicate an opportunity to improvement
performance by adding permanent indices that do not need to be reinitialized
each time the statement is run.
.It SQLITE_STMTSTATUS_VM_STEP
This is the number of virtual machine operations executed by the prepared
statement if that number is less than or equal to 2147483647.
The number of virtual machine operations can be used as a proxy for
the total work done by the prepared statement.
If the number of virtual machine operations exceeds 2147483647 then
the value returned by this statement status code is undefined.
.It SQLITE_STMTSTATUS_REPREPARE
This is the number of times that the prepare statement has been automatically
regenerated due to schema changes or change to bound parameters
that might affect the query plan.
.It SQLITE_STMTSTATUS_RUN
This is the number of times that the prepared statement has been run.
A single "run" for the purposes of this counter is one or more calls
to sqlite3_step() followed by a call to sqlite3_reset().
The counter is incremented on the first sqlite3_step()
call of each cycle.
.It SQLITE_STMTSTATUS_MEMUSED
This is the approximate number of bytes of heap memory used to store
the prepared statement.
This value is not actually a counter, and so the resetFlg parameter
to sqlite3_stmt_status() is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
.El
.Pp
.Sh SEE ALSO
.Xr sqlite3_reset 3 ,
.Xr sqlite3_step 3 ,
.Xr sqlite3_stmt_status 3