MDEV-15461 Check Constraints with binary logging makes insert inconsistent

Problem was that verify_constraints() didn't check if
there was an error as part of evaluating constraints
(can happen in strict mode).

In one-row-insert the error was ignored when using
binary logging as binary logging clear errors if insert
succeeded. In multi-row-insert the error was noticed
for the second row.

After this fix one will get an error for both one and
multi-row inserts if the constraints generates a warning
in strict mode.

1 files changed, 18 insertions, 3 deletions

diff --git a/sql/table.cc b/sql/table.cc
index fff2be4f154..d7cbf555b72 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -5116,14 +5116,25 @@ int TABLE_LIST::view_check_option(THD *thd, bool ignore_failure)
 
 int TABLE::verify_constraints(bool ignore_failure)
 {
+  /*
+    We have to check is_error() first as we are checking it for each
+    constraint to catch fatal warnings.
+  */
+  if (in_use->is_error())
+    return (VIEW_CHECK_ERROR);
+
   /* go trough check option clauses for fields and table */
   if (check_constraints &&
       !(in_use->variables.option_bits & OPTION_NO_CHECK_CONSTRAINT_CHECKS))
   {
     for (Virtual_column_info **chk= check_constraints ; *chk ; chk++)
     {
-      /* yes! NULL is ok, see 4.23.3.4 Table check constraints, part 2, SQL:2016 */
-      if ((*chk)->expr->val_int() == 0 && !(*chk)->expr->null_value)
+      /*
+        yes! NULL is ok.
+        see 4.23.3.4 Table check constraints, part 2, SQL:2016
+      */
+      if (((*chk)->expr->val_int() == 0 && !(*chk)->expr->null_value) ||
+          in_use->is_error())
       {
         my_error(ER_CONSTRAINT_FAILED,
                  MYF(ignore_failure ? ME_JUST_WARNING : 0), (*chk)->name.str,
@@ -5132,7 +5143,11 @@ int TABLE::verify_constraints(bool ignore_failure)
       }
     }
   }
-  return(VIEW_CHECK_OK);
+  /*
+    We have to check in_use() as checking constraints may have generated
+    warnings that should be treated as errors
+  */
+  return(!in_use->is_error() ? VIEW_CHECK_OK : VIEW_CHECK_ERROR);
 }