SQLite

   ovfl_pages int,   -- Number of overflow pages used
   int_unused int,   -- Number of unused bytes on interior pages
   leaf_unused int,  -- Number of unused bytes on primary pages
   ovfl_unused int   -- Number of unused bytes on overflow pages
);}
mem eval $tabledef

proc integerify {real} {
  return [expr int($real)]
}
mem function int integerify

# Quote a string for use in an SQL query. Examples:
#
# [quote {hello world}]   == {'hello world'}
# [quote {hello world's}] == {'hello world''s'}
#
proc quote {txt} {
  regsub -all ' $txt '' q

    return [format {%5.1f%% %s} $v $of]
  } elseif {$v<0.1 || $v>99.9} {
    return [format {%7.3f%% %s} $v $of]
  } else {
    return [format {%6.2f%% %s} $v $of]
  }
}

proc divide {num denom} {
  if {$denom==0} {return 0.0}
  return [format %.2f [expr double($num)/double($denom)]]
}

# Generate a subreport that covers some subset of the database.
# the $where clause determines which subset to analyze.
#
proc subreport {title where} {
  global pageSize file_pgcnt

  # Query the in-memory database for the sum of various statistics 
  # for the subset of tables/indices identified by the WHERE clause in
  # $where. Note that even if the WHERE clause matches no rows, the
  # following query returns exactly one row (because it is an aggregate).
  #
  # The results of the query are stored directly by SQLite into local 
  # variables (i.e. $nentry, $nleaf etc.).
  #
  mem eval "
    SELECT
      int(sum(nentry)) AS nentry,
      int(sum(leaf_entries)) AS nleaf,
      int(sum(payload)) AS payload,
      int(sum(ovfl_payload)) AS ovfl_payload,
      max(mx_payload) AS mx_payload,
      int(sum(ovfl_cnt)) as ovfl_cnt,
      int(sum(leaf_pages)) AS leaf_pages,
      int(sum(int_pages)) AS int_pages,
      int(sum(ovfl_pages)) AS ovfl_pages,
      int(sum(leaf_unused)) AS leaf_unused,
      int(sum(int_unused)) AS int_unused,
      int(sum(ovfl_unused)) AS ovfl_unused
    FROM space_used WHERE $where" {} {}

  # Output the sub-report title, nicely decorated with * characters.
  #
  puts ""
  set len [string length $title]
  set stars [string repeat * [expr 65-$len]]

  # ovfl_cnt_percent: Percentage of btree entries that use overflow pages.
  #
  set total_pages [expr {$leaf_pages+$int_pages+$ovfl_pages}]
  set total_pages_percent [percent $total_pages $file_pgcnt]
  set storage [expr {$total_pages*$pageSize}]
  set payload_percent [percent $payload $storage {of storage consumed}]
  set total_unused [expr {$ovfl_unused+$int_unused+$leaf_unused}]
  set avg_payload [divide $payload $nleaf]
  set avg_unused [divide $total_unused $nleaf]
  if {$int_pages>0} {
    # TODO: Is this formula correct?
    set nTab [mem eval "
      SELECT count(*) FROM (
          SELECT DISTINCT tblname FROM space_used WHERE $where AND is_index=0
      )
    "]
    set avg_fanout [mem eval "
      SELECT (sum(leaf_pages+int_pages)-$nTab)/sum(int_pages) FROM space_used
          WHERE $where AND is_index = 0
    "]
    set avg_fanout [format %.2f $avg_fanout]
  }
  set ovfl_cnt_percent [percent $ovfl_cnt $nleaf {of all entries}]

  # Print out the sub-report statistics.
  #
  statline {Percentage of total database} $total_pages_percent
  statline {Number of entries} $nleaf

set file_bytes  [file size $file_to_analyze]
set file_pgcnt  [expr {$file_bytes/$pageSize}]

set av_pgcnt    [autovacuum_overhead $file_pgcnt $pageSize]
set av_percent  [percent $av_pgcnt $file_pgcnt]

set sql {SELECT sum(leaf_pages+int_pages+ovfl_pages) FROM space_used}
set inuse_pgcnt   [expr int([mem eval $sql])]
set inuse_percent [percent $inuse_pgcnt $file_pgcnt]

set free_pgcnt    [expr $file_pgcnt-$inuse_pgcnt-$av_pgcnt]
set free_percent  [percent $free_pgcnt $file_pgcnt]
set free_pgcnt2   [lindex [btree_get_meta $DB] 0]
set free_percent2 [percent $free_pgcnt2 $file_pgcnt]

set file_pgcnt2 [expr {$inuse_pgcnt+$free_pgcnt2+$av_pgcnt}]

set ntable [db eval {SELECT count(*)+1 FROM sqlite_master WHERE type='table'}]
set nindex [db eval {SELECT count(*) FROM sqlite_master WHERE type='index'}]
set sql {SELECT count(*) FROM sqlite_master WHERE name LIKE 'sqlite_autoindex%'}
set nautoindex [db eval $sql]
set nmanindex [expr {$nindex-$nautoindex}]

# set total_payload [mem eval "SELECT sum(payload) FROM space_used"]
set user_payload [mem one {SELECT int(sum(payload)) FROM space_used
     WHERE NOT is_index AND name NOT LIKE 'sqlite_master'}]
set user_percent [percent $user_payload $file_bytes]

# Output the summary statistics calculated above.
#
puts "/** Disk-Space Utilization Report For $file_to_analyze"
puts "*** As of [clock format [clock seconds] -format {%Y-%b-%d %H:%M:%S}]"

# Output table rankings
#
puts ""
puts "*** Page counts for all tables with their indices ********************"
puts ""
mem eval {SELECT tblname, count(*) AS cnt, 
              int(sum(int_pages+leaf_pages+ovfl_pages)) AS size
          FROM space_used GROUP BY tblname ORDER BY size DESC, tblname} {} {
  statline [string toupper $tblname] $size [percent $size $file_pgcnt]
}

# Output subreports
#
if {$nindex>0} {