SQLite

# by reading the contents of a named table (te_read_tbl), or by executing
# a SELECT statement (t3_read_sql).  
#
# See the comment above, describing "te_* commands", for details of the
# return values.
#
proc te_read_tbl {db tbl} {
 te_read_sql $db "SELECT * FROM '$tbl'"
}
proc te_read_sql {db sql} {
  set S [sqlite3_prepare_v2 $db $sql -1 DUMMY]

  set cols [list]
  for {set i 0} {$i < [sqlite3_column_count $S]} {incr i} {
    lappend cols [sqlite3_column_name $S $i]

  
  list $cret $rret
}

proc te_tbljoin {db t1 t2 args} {
  te_join [te_read_tbl $db $t1] [te_read_tbl $db $t2] {*}$args
}

proc te_apply_affinity {affinity typevar valvar} {
  upvar $typevar type
  upvar $valvar val

  switch -- $affinity {
    integer {
      if {[string is double $val]} { set type REAL }
      if {[string is wideinteger $val]} { set type INTEGER }
      if {$type == "REAL" && int($val)==$val} { 
        set type INTEGER 
        set val [expr {int($val)}]
      }
    }
    text {
      set type TEXT
    }
    none { }

    default { error "invalid affinity: $affinity" }
  }
}

#----------
# te_equals ?SWITCHES? c1 c2 cols1 row1 cols2 row2
#
proc te_equals {args} {

  if {[llength $args]<6} {error "invalid arguments to te_equals"}
  foreach {c1 c2 cols1 row1 cols2 row2} [lrange $args end-5 end] break

  set nocase 0
  set affinity none

  for {set i 0} {$i < ([llength $args]-6)} {incr i} {
    set a [lindex $args $i]
    switch -- $a {
      -nocase {
        set nocase 1
      }
      -affinity {
        set affinity [string tolower [lindex $args [incr i]]]
      }
      default {
        error "invalid arguments to te_equals"
      }
    }
  }

  set idx2 [if {[string is integer $c2]} { set c2 } else { lsearch $cols2 $c2 }]
  set idx1 [if {[string is integer $c1]} { set c1 } else { lsearch $cols1 $c1 }]

  set t1 [lindex $row1 $idx1 0]
  set t2 [lindex $row2 $idx2 0]
  set v1 [lindex $row1 $idx1 1]
  set v2 [lindex $row2 $idx2 1]

  te_apply_affinity $affinity t1 v1
  te_apply_affinity $affinity t2 v2

  if {$t1 == "NULL" || $t2 == "NULL"} { return 0 }
  if {$nocase && $t1 == "TEXT"} { set v1 [string tolower $v1] }
  if {$nocase && $t2 == "TEXT"} { set v2 [string tolower $v2] }


  set res [expr {$t1 == $t2 && [string equal $v1 $v2]}]
  return $res
}

proc te_false {args} { return 0 }
proc te_true  {args} { return 1 }

proc te_and {args} {
  foreach a [lrange $args 0 end-4] {

  INSERT INTO t3 VALUES('a');
  INSERT INTO t3 VALUES('c');
  INSERT INTO t3 VALUES('b');
} {}

foreach {tn indexes} {
  e_select-2.1.1 { }
  e_select-2.1.2 { CREATE INDEX i1 ON t1(a) }
  e_select-2.1.3 { CREATE INDEX i1 ON t2(a) }
  e_select-2.1.4 { CREATE INDEX i1 ON t3(b) }
} {

  catchsql { DROP INDEX i1 }
  catchsql { DROP INDEX i2 }
  catchsql { DROP INDEX i3 }
  execsql $indexes

  te_dataset_eq_unordered $tn.28d [
    te_read_sql db "SELECT * FROM t3 NATURAL LEFT JOIN (t2 NATURAL JOIN t1)"
  ] [te_join $t3 $t2_natural_join_t1                                       \
      -left -using {b} -on {te_equals -nocase b b}                         \
  ]
}

do_execsql_test e_select-2.2.0 {
  CREATE TABLE t4(x TEXT COLLATE nocase);
  CREATE TABLE t5(y INTEGER, z TEXT COLLATE binary);

  INSERT INTO t4 VALUES('2.0');
  INSERT INTO t4 VALUES('TWO');
  INSERT INTO t5 VALUES(2, 'two');
} {}

# EVIDENCE-OF: R-55824-40976 A sub-select specified in the join-source
# following the FROM clause in a simple SELECT statement is handled as
# if it was a table containing the data returned by executing the
# sub-select statement.
#
# EVIDENCE-OF: R-42612-06757 Each column of the sub-select dataset
# inherits the collation sequence and affinity of the corresponding
# expression in the sub-select statement.
#
foreach {tn subselect select spec} {
  1   "SELECT * FROM t2"   "SELECT * FROM t1 JOIN %ss%" 
    {t1 %ss%}

  2   "SELECT * FROM t2"   "SELECT * FROM t1 JOIN %ss% AS x ON (t1.a=x.a)" 
      {t1 %ss% -on {te_equals 0 0}}

  3   "SELECT * FROM t2"   "SELECT * FROM %ss% AS x JOIN t1 ON (t1.a=x.a)" 
      {%ss% t1 -on {te_equals 0 0}}

  4   "SELECT * FROM t1, t2" "SELECT * FROM %ss% AS x JOIN t3"
      {%ss% t3}

  5   "SELECT * FROM t1, t2" "SELECT * FROM %ss% NATURAL JOIN t3"
      {%ss% t3 -using b -on {te_equals 1 0}}

  6   "SELECT * FROM t1, t2" "SELECT * FROM t3 NATURAL JOIN %ss%"
      {t3 %ss% -using b -on {te_equals -nocase 0 1}}

  7   "SELECT * FROM t1, t2" "SELECT * FROM t3 NATURAL LEFT JOIN %ss%"
      {t3 %ss% -left -using b -on {te_equals -nocase 0 1}}

  8   "SELECT count(*) AS y FROM t4"   "SELECT * FROM t5, %ss% USING (y)"
      {t5 %ss% -using y -on {te_equals -affinity text 0 0}}

  9   "SELECT count(*) AS y FROM t4"   "SELECT * FROM %ss%, t5 USING (y)"
      {%ss% t5 -using y -on {te_equals -affinity text 0 0}}

  10  "SELECT x AS y FROM t4"   "SELECT * FROM %ss% JOIN t5 USING (y)"
      {%ss% t5 -using y -on {te_equals -nocase -affinity integer 0 0}}

  11  "SELECT x AS y FROM t4"   "SELECT * FROM t5 JOIN %ss% USING (y)"
      {t5 %ss% -using y -on {te_equals -nocase -affinity integer 0 0}}

  12  "SELECT y AS x FROM t5"   "SELECT * FROM %ss% JOIN t4 USING (x)"
      {%ss% t4 -using x -on {te_equals -nocase -affinity integer 0 0}}

  13  "SELECT y AS x FROM t5"   "SELECT * FROM t4 JOIN %ss% USING (x)"
      {t4 %ss% -using x -on {te_equals -nocase -affinity integer 0 0}}

  14  "SELECT +y AS x FROM t5"   "SELECT * FROM %ss% JOIN t4 USING (x)"
      {%ss% t4 -using x -on {te_equals -nocase -affinity text 0 0}}

  15  "SELECT +y AS x FROM t5"   "SELECT * FROM t4 JOIN %ss% USING (x)"
      {t4 %ss% -using x -on {te_equals -nocase -affinity text 0 0}}
} {

  # Create a temporary table named %ss% containing the data returned by
  # the sub-select. Then have the [te_tbljoin] proc use this table to
  # compute the expected results of the $select query. Drop the temporary
  # table before continuing.
  #
  execsql "CREATE TEMP TABLE '%ss%' AS $subselect"
  set te [eval te_tbljoin db $spec]
  execsql "DROP TABLE '%ss%'"

  # Check that the actual data returned by the $select query is the same
  # as the expected data calculated using [te_tbljoin] above.
  #
  te_dataset_eq_unordered e_select-2.2.1.$tn [
    te_read_sql db [string map [list %ss% "($subselect)"] $select]
  ] $te
}

finish_test