AryaWu/sqlite

1# 2024-08-032#3# The author disclaims copyright to this source code.  In place of4# a legal notice, here is a blessing:5#6#    May you do good and not evil.7#    May you find forgiveness for yourself and forgive others.8#    May you share freely, never taking more than you give.9#10#***********************************************************************11# 12#13 14set testdir [file dirname $argv0]15source $testdir/tester.tcl16set testprefix bestindexD17 18ifcapable !vtab {19  finish_test20  return21}22 23register_tcl_module db24 25proc vtab_command {method args} {26  switch -- $method {27    xConnect {28      return "CREATE TABLE t1(a PRIMARY KEY, b, c) WITHOUT ROWID"29    }30 31    xBestIndex {32      set hdl [lindex $args 0]33      set ::colUsed [$hdl mask]34 35      set cost 100000036      set used ""37 38      set cons 039      foreach c [$hdl constraints] {40        set cost [expr $cost/10]41        append used " use $cons"42        incr cons43      }44 45      return "cost $cost rows $cost $used"46    }47  }48 49  return {}50}51 52do_execsql_test 1.0 {53  CREATE VIRTUAL TABLE x1 USING tcl(vtab_command);54 55  CREATE TABLE t2(a, b);56} {}57 58# This proc assumes that there is only one use of a virtual table - x1 -59# in SQL statement $sql. It tests that the colUsed value passed to the60# xBestIndex method matches the actual columns used, which is ascertained 61# by searching the compiled VM code for VColumn instructions.62#63proc do_colsused_test {tn sql} {64  set ::colUsed ""65  execsql $sql66  set got $::colUsed67 68  set expect 069  db eval "EXPLAIN $sql" x {70    if {$x(opcode)=="VColumn"} {71      set expect [expr $expect | (1<<$x(p2))]72    }73  }74 75  uplevel [list do_test $tn.($expect/$got) [list expr ($expect & $got)] $expect]76}77 78do_colsused_test 1.1 { SELECT a FROM x1 }   79do_colsused_test 1.2 { SELECT a,c FROM x1 } 80do_colsused_test 1.3 { SELECT b FROM x1 }   81do_colsused_test 1.4 { SELECT b FROM x1 WHERE c=? } 82 83do_colsused_test 1.5 {84  select 1 from t2 full join x1;85}86 87do_colsused_test 1.6 {88  select 1 from x1 WHERE (b=? AND c=?) OR (b=? AND c=?)89}90 91finish_test92 93 94