MDEV-35673 Item_subselect::used_tables_cache: outer-reference name resolution and query-merge maintenance

client/mysqltest.cc

@@ -12549,6 +12549,7 @@ void init_re(void)
       "^("
       "[[:space:]]*PREPARE[[:space:]]|"
       "[[:space:]]*EXECUTE[[:space:]]|"
+      "[[:space:]]*EXPLAIN[[:space:]]+EXTENDED[[:space:]]|"
       "[[:space:]]*DEALLOCATE[[:space:]]+PREPARE[[:space:]]|"
       "[[:space:]]*DROP[[:space:]]+PREPARE[[:space:]]|"
       "(SET[[:space:]]+STATEMENT[[:space:]]+.+[[:space:]]+FOR[[:space:]]+)?"

mysql-test/include/evw_capture.inc

@@ -0,0 +1,57 @@
+# Capture one execution method of $EVW_QRY into the file $EVW_OUT.
+#
+# Used by main/execute_various_ways.inc to cross-check that a query run
+# several different ways returns the same rows.
+#
+# The statements are piped through a fresh mysql client session (so the
+# real PREPARE/EXECUTE and CALL paths are exercised, unlike a backtick
+# capture which only returns the first row, or a CREATE/INSERT ... SELECT
+# sink which would change sql_command away from SQLCOM_SELECT).
+#
+# A marker row is emitted immediately before the row-producing statement;
+# only the lines after the LAST marker are kept.  For the prepared
+# statement and stored procedure methods this isolates the *2nd* execution
+# (the one MDEV-35673 is about).  Kept rows are sorted, so row order does
+# not need to be deterministic in $EVW_QRY.
+#
+# In (environment variables, set with `--let NAME= value`):
+#   MYSQL        - the mysql client command (exported by mtr)
+#   EVW_DB       - database to run in
+#   EVW_QRY      - the query under test.  It is interpolated into SQL built
+#                  here (e.g. prepare s from '$q'), so it must contain no
+#                  interior ';' and no single quote (').
+#   EVW_METHOD   - 0..5, selects the execution method
+#   EVW_MARKER   - marker string separating discarded from kept output
+#   EVW_OUT      - output file for the normalised rows
+
+perl;
+  my ($mysql,$db,$q,$m,$mark,$out) =
+     @ENV{qw(MYSQL EVW_DB EVW_QRY EVW_METHOD EVW_MARKER EVW_OUT)};
+
+  my $sel;
+  if    ($m==0){ $sel="select '$mark'; $q"; }
+  elsif ($m==1){ $sel="prepare s from '$q'; execute s; select '$mark'; execute s; deallocate prepare s"; }
+  elsif ($m==2){ $sel="select '$mark'; select * from ($q) dt"; }
+  elsif ($m==3){ $sel="create view evw_v as $q; select '$mark'; select * from evw_v; drop view evw_v"; }
+  elsif ($m==4){ $sel="select '$mark'; with cte as ($q) select * from cte"; }
+  elsif ($m==5){ $sel="create procedure evw_p() $q; call evw_p(); select '$mark'; call evw_p(); drop procedure evw_p"; }
+  else         { die "evw_capture.inc: bad EVW_METHOD '$m'"; }
+
+  my $raw="$out.raw";
+  # stderr is folded into the capture (2>&1); a method that errors *before*
+  # the marker would yield empty output, so this relies on the visible
+  # section of execute_various_ways.inc running first and aborting the test
+  # on any unexpected error.
+  open(P,"| $mysql --batch --skip-column-names $db > $raw 2>&1")
+      or die "evw_capture.inc: pipe to mysql: $!";
+  print P "$sel;\n" or die "evw_capture.inc: write to mysql: $!";
+  close(P) or die "evw_capture.inc: mysql client failed (exit $?) for method $m";
+
+  open(R,"<",$raw) or die "evw_capture.inc: read $raw: $!";
+  my @l=<R>; close(R); unlink $raw;
+  my $start=0;
+  for my $i (0..$#l){ $start=$i+1 if $l[$i]=~/\Q$mark\E/; }
+  my @rows= sort @l[$start..$#l];
+  open(W,">",$out) or die "evw_capture.inc: write $out: $!";
+  print W @rows; close(W);
+EOF

mysql-test/main/derived_cond_pushdown.test

@@ -1896,9 +1896,7 @@ DELIMITER ;$$
 CALL p1('a');
 DROP PROCEDURE p1;
 
---disable_ps2_protocol
 SELECT a FROM (SELECT "aa" a) t WHERE REGEXP_INSTR(t.a, (SELECT MAX('aa') FROM DUAL LIMIT 1));
---enable_ps2_protocol
 
 DELIMITER $$;
 CREATE OR REPLACE FUNCTION f1(a VARCHAR(10), b VARCHAR(10)) RETURNS INT

mysql-test/main/execute_various_ways.inc

@@ -0,0 +1,53 @@
+# Run $qry six different ways, echo each to the result log (as before),
+# then capture each method's result set and assert they are all
+# row-for-row identical.  See include/evw_capture.inc for how/why the
+# capture is done through the mysql client rather than backticks or a
+# table sink.
+#
+# In:  $ver  - label for this group
+#      $qry  - the query under test (no interior ';')
+
+# ---- visible executions: unchanged, still populate the .result file ----
+echo test $ver.0;
+eval $qry;
+echo test $ver.1;
+eval prepare s from '$qry';
+execute s;
+execute s;
+deallocate prepare s;
+echo test $ver.2;
+eval select * from ($qry) dt;
+echo test $ver.3;
+eval create view v as $qry;
+select * from v;
+select * from v;
+drop view v;
+echo test $ver.4;
+eval with cte as ($qry) select * from cte;
+echo test $ver.5;
+eval create procedure p() $qry;
+call p();
+call p();
+drop procedure p;
+
+# ---- cross-check: every method must return the same rows as method 0 ----
+--let EVW_MARKER= __EVW_ROWS__
+--let EVW_QRY= $qry
+--let EVW_DB= `select database()`
+
+--let $m= 0
+while ($m <= 5)
+{
+  --let EVW_METHOD= $m
+  --let EVW_OUT= $MYSQLTEST_VARDIR/tmp/evw_$m.tsv
+  --source include/evw_capture.inc
+  --inc $m
+}
+
+--diff_files $MYSQLTEST_VARDIR/tmp/evw_0.tsv $MYSQLTEST_VARDIR/tmp/evw_1.tsv
+--diff_files $MYSQLTEST_VARDIR/tmp/evw_0.tsv $MYSQLTEST_VARDIR/tmp/evw_2.tsv
+--diff_files $MYSQLTEST_VARDIR/tmp/evw_0.tsv $MYSQLTEST_VARDIR/tmp/evw_3.tsv
+--diff_files $MYSQLTEST_VARDIR/tmp/evw_0.tsv $MYSQLTEST_VARDIR/tmp/evw_4.tsv
+--diff_files $MYSQLTEST_VARDIR/tmp/evw_0.tsv $MYSQLTEST_VARDIR/tmp/evw_5.tsv
+
+echo "END GROUP";

mysql-test/main/features.test

@@ -77,7 +77,7 @@ create table t1 (a int);
 insert into t1 values (2);
 select (select a from t1 where t1.a=t2.a), a from t1 as t2;
 drop table t1;
---replace_result 8 4
+--replace_result 8 5
 show status like "feature_subquery";
 
 --echo #

mysql-test/main/having_cond_pushdown.test

@@ -1451,11 +1451,9 @@ DROP TABLE t1,t2;
 
 CREATE TABLE t1 (i int NOT NULL);
 SELECT * FROM t1 GROUP BY i HAVING i IN ( i IS NULL);
-#dublicate warning
---disable_view_protocol
+#duplicate warning
 SELECT * FROM t1 GROUP BY i HAVING i IN ( i IS NULL AND 'x' = 0);
 SELECT * FROM t1 GROUP BY i HAVING i='1' IN ( i IS NULL AND 'x' = 0);
---enable_view_protocol
 DROP TABLE t1;
 
 --echo #