Fixed bug#10977: No warning issued if a column name is truncated

When an alias is set to a column leading spaces are removed from the alias.
But when this is done on aliases set by user this can lead to confusion.

Now Item::set_name() method issues the warning if leading spaces were removed
from an alias set by user.

New warning message is added.

1 files changed, 6 insertions, 0 deletions

diff --git a/sql/item.cc b/sql/item.cc
index 511ea1ffb44..ad8b79182d4 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -573,6 +573,7 @@ void Item::set_name(const char *str, uint length, CHARSET_INFO *cs)
   }
   if (cs->ctype)
   {
+    uint orig_len= length;
     /*
       This will probably need a better implementation in the future:
       a function in CHARSET_INFO structure.
@@ -582,6 +583,11 @@ void Item::set_name(const char *str, uint length, CHARSET_INFO *cs)
       length--;
       str++;
     }
+    if (orig_len != length && !is_autogenerated_name)
+      push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
+                          ER_REMOVED_SPACES, ER(ER_REMOVED_SPACES),
+                          str + length - orig_len);
+
   }
   if (!my_charset_same(cs, system_charset_info))
   {