MDEV-30946 Index usage for DATE(datetime_column) = const does not work for DELETE and UPDATEpreview-11.1-mdev-8320

Add date conditions transformation to the execution paths
of DELETE and UPDATE commands.

Strip excessive prepared statements from the test file

1 files changed, 6 insertions, 0 deletions

diff --git a/sql/sql_update.cc b/sql/sql_update.cc
index ff1d70e7f8e..2be2a85b889 100644
--- a/sql/sql_update.cc
+++ b/sql/sql_update.cc
@@ -433,6 +433,12 @@ bool Sql_cmd_update::update_single_table(THD *thd)
         goto produce_explain_and_leave;
     }
   }
+  if (conds && thd->lex->are_date_funcs_used())
+  {
+    /* Rewrite datetime comparison conditions into sargable */
+    conds= conds->top_level_transform(thd, &Item::date_conds_transformer,
+                                      (uchar *) 0);
+  }
 
   // Don't count on usage of 'only index' when calculating which key to use
   table->covering_keys.clear_all();