Updated: 2022/Sep/29

Please read Privacy Policy. It's for your privacy.

SQLITE_SCANSTAT_NLOOP(3)   Library Functions Manual   SQLITE_SCANSTAT_NLOOP(3)

NAME
     SQLITE_SCANSTAT_NLOOP, SQLITE_SCANSTAT_NVISIT, SQLITE_SCANSTAT_EST,
     SQLITE_SCANSTAT_NAME, SQLITE_SCANSTAT_EXPLAIN, SQLITE_SCANSTAT_SELECTID,
     SQLITE_SCANSTAT_PARENTID, SQLITE_SCANSTAT_NCYCLE - prepared statement
     scan status opcodes

SYNOPSIS
     #include <sqlite3.h>

     #define SQLITE_SCANSTAT_NLOOP
     #define SQLITE_SCANSTAT_NVISIT
     #define SQLITE_SCANSTAT_EST
     #define SQLITE_SCANSTAT_NAME
     #define SQLITE_SCANSTAT_EXPLAIN
     #define SQLITE_SCANSTAT_SELECTID
     #define SQLITE_SCANSTAT_PARENTID
     #define SQLITE_SCANSTAT_NCYCLE

DESCRIPTION
     The following constants can be used for the T parameter to the
     sqlite3_stmt_scanstatus(S,X,T,V) interface.  Each constant designates a
     different metric for sqlite3_stmt_scanstatus() to return.

     When the value returned to V is a string, space to hold that string is
     managed by the prepared statement S and will be automatically freed when
     S is finalized.

     Not all values are available for all query elements.  When a value is not
     available, the output variable is set to -1 if the value is numeric, or
     to NULL if it is a string (SQLITE_SCANSTAT_NAME).

     SQLITE_SCANSTAT_NLOOP
             The sqlite3_int64 variable pointed to by the V parameter will be
             set to the total number of times that the X-th loop has run.

     SQLITE_SCANSTAT_NVISIT
             The sqlite3_int64 variable pointed to by the V parameter will be
             set to the total number of rows examined by all iterations of the
             X-th loop.

     SQLITE_SCANSTAT_EST
             The "double" variable pointed to by the V parameter will be set
             to the query planner's estimate for the average number of rows
             output from each iteration of the X-th loop.  If the query
             planner's estimates was accurate, then this value will
             approximate the quotient NVISIT/NLOOP and the product of this
             value for all prior loops with the same SELECTID will be the
             NLOOP value for the current loop.

     SQLITE_SCANSTAT_NAME
             The "const char *" variable pointed to by the V parameter will be
             set to a zero-terminated UTF-8 string containing the name of the
             index or table used for the X-th loop.

     SQLITE_SCANSTAT_EXPLAIN
             The "const char *" variable pointed to by the V parameter will be
             set to a zero-terminated UTF-8 string containing the EXPLAIN
             QUERY PLAN description for the X-th loop.

     SQLITE_SCANSTAT_SELECTID
             The "int" variable pointed to by the V parameter will be set to
             the id for the X-th query plan element.  The id value is unique
             within the statement.  The select-id is the same value as is
             output in the first column of an EXPLAIN QUERY PLAN query.

     SQLITE_SCANSTAT_PARENTID
             The "int" variable pointed to by the V parameter will be set to
             the the id of the parent of the current query element, if
             applicable, or to zero if the query element has no parent.  This
             is the same value as returned in the second column of an EXPLAIN
             QUERY PLAN query.

     SQLITE_SCANSTAT_NCYCLE
             The sqlite3_int64 output value is set to the number of cycles,
             according to the processor time-stamp counter, that elapsed while
             the query element was being processed.  This value is not
             available for all query elements - if it is unavailable the
             output variable is set to -1.

IMPLEMENTATION NOTES
     These declarations were extracted from the interface documentation at
     line 10031.

     #define SQLITE_SCANSTAT_NLOOP    0
     #define SQLITE_SCANSTAT_NVISIT   1
     #define SQLITE_SCANSTAT_EST      2
     #define SQLITE_SCANSTAT_NAME     3
     #define SQLITE_SCANSTAT_EXPLAIN  4
     #define SQLITE_SCANSTAT_SELECTID 5
     #define SQLITE_SCANSTAT_PARENTID 6
     #define SQLITE_SCANSTAT_NCYCLE   7

SEE ALSO
     sqlite_int64(3)

NetBSD 10.99                    August 24, 2023                   NetBSD 10.99