# 2018-09-09
#
# The author disclaims copyright to this source code. In place of
# a legal notice, here is a blessing:
#
# May you do good and not evil.
# May you find forgiveness for yourself and forgive others.
# May you share freely, never taking more than you give.
#
#***********************************************************************
#
set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix bestindex6
ifcapable !vtab {
finish_test
return
}
register_tcl_module db
proc vtab_command {src method args} {
switch -- $method {
xConnect {
return [db one {SELECT sql FROM sqlite_master where name = $src}]
}
xBestIndex {
set clist [lindex $args 0]
set wlist 1
set iCons 0
set ret [list]
foreach cons $clist {
catch { array unset C }
array set C $cons
if {$C(usable)} {
set col [db one {
SELECT name FROM pragma_table_info($src) WHERE cid=$C(column)
}]
switch $C(op) {
isnull {
lappend wlist "$col IS NULL"
lappend ret omit $iCons
}
eq {
lappend wlist "$col = %$iCons%"
lappend ret omit $iCons
}
}
}
incr iCons
}
#puts "xBestIndex: $ret"
lappend ret idxStr [join $wlist " AND "]
return $ret
}
xFilter {
foreach {idxnum idxstr aa} $args {}
set map [list]
for {set iCons 0} {$iCons < [llength $aa]} {incr iCons} {
lappend map %$iCons% [lindex $aa $iCons]
}
set ret [list sql \
"SELECT rowid, * FROM $src WHERE [string map $map $idxstr]"
]
# puts "xFilter: $ret"
return $ret
}
}
return {}
}
do_execsql_test 1.0 {
CREATE TABLE t1(id int, value text);
CREATE TABLE t2(ctx int, id int, value text);
INSERT INTO t1 VALUES(1,'try');
INSERT INTO t2 VALUES(1,1,'good');
INSERT INTO t2 VALUES(2,2,'evil');
CREATE VIRTUAL TABLE vt1 USING tcl(vtab_command t1);
CREATE VIRTUAL TABLE vt2 USING tcl(vtab_command t2);
}
do_execsql_test 1.1 {
select * from t2 left join t1 on t1.id=t2.ctx where t1.value is null;
} {2 2 evil {} {}}
do_execsql_test 1.2 {
select * from vt2 left join vt1 on vt1.id=vt2.ctx where vt1.value is null;
} {2 2 evil {} {}}
unset -nocomplain xxx
do_execsql_test 1.3 {
select * from vt2 left join vt1 on vt1.id=vt2.ctx where vt1.value is $xxx;
} {2 2 evil {} {}}
do_execsql_test 1.4 {
select * from t2 left join vt1 on vt1.id=t2.ctx where vt1.value = 3
} {}
finish_test