MDEV-18880: Optimizer trace prints date in hexadecimal

Introduced a print_key_value function to makes sure that the trace prints data in readable format
for readable characters and the rest of the characters are printed as hexadecimal.

1 files changed, 3 insertions, 0 deletions

diff --git a/sql/sql_string.h b/sql/sql_string.h
index caefee7ec09..d8edf5e81f0 100644
--- a/sql/sql_string.h
+++ b/sql/sql_string.h
@@ -674,6 +674,7 @@ public:
 
   int reserve(size_t space_needed)
   {
+    DBUG_ASSERT((ulonglong) str_length + space_needed < UINT_MAX32);
     return realloc(str_length + space_needed);
   }
   int reserve(size_t space_needed, size_t grow_by);
@@ -959,6 +960,8 @@ public:
   {
     return !sortcmp(this, other, cs);
   }
+private:
+  bool append_semi_hex(const char *s, uint len, CHARSET_INFO *cs);
 };