Most of the groundwork for sprint task 729 (implement FUNCTIONs).

Expanded the mysql.proc table, reworked the find/create/drop functions
completely, added new functions for FUNCTIONs (lotta functions here :),
got rid of some unnecessary use of Item_strings while at it. Extended
the parser correspondingly, and fiddled around a bit to make SP FUNCTIONs
coexist with UDFs.
Can now CREATE and DROP FUNCTIONs. Invoking yet to come...


Docs/sp-implemented.txt:
  Updated with info about CASCADE/RESTICT and METHOD, and some answers to questions.
include/mysqld_error.h:
  New error message for misuse of RETURN.
mysql-test/install_test_db.sh:
  Added enum field to mysql.proc to distinguish between FUNCTION and PROCEDURE.
mysql-test/r/sp.result:
  New test for creating and dropping FUNCTIONS.
mysql-test/t/sp.test:
  New test for creating and dropping FUNCTIONS.
scripts/mysql_install_db.sh:
  Added enum field to mysql.proc to distinguish between FUNCTION and PROCEDURE.
sql/lex.h:
  De-UDFed some symbol names, as they are now used for SPs as well.
  Added RETURN_SYM.
sql/share/czech/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/danish/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/dutch/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/english/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/estonian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/french/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/german/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/greek/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/hungarian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/italian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/japanese/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/korean/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/norwegian-ny/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/norwegian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/polish/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/portuguese/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/romanian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/russian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/serbian/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/slovak/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/spanish/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/swedish/errmsg.txt:
  New error message for misuse of RETURN.
sql/share/ukrainian/errmsg.txt:
  New error message for misuse of RETURN.
sql/sp.cc:
  Major rehack to accomodate FUNCTIONs, and to make it easier to add
  future in-memory cache of prepared SPs.
sql/sp.h:
  Major rehack to accomodate FUNCTIONs, and to make it easier to add
  future in-memory cache of prepared SPs.
sql/sp_head.cc:
  Now creates FUNCTIONs too. (And got rid of some unnecessary Item_string use.)
sql/sp_head.h:
  Now creates FUNCTIONs too. (And got rid of some unnecessary Item_string use.)
sql/sql_lex.h:
  New stored FUNCTION commands.
sql/sql_parse.cc:
  Added FUNCTION support ("drop" merged with the old UDF code), and made some
  additional changes for better error handling (following the sp.cc rehacking).
sql/sql_yacc.yy:
  Some former UDF specific symbols renamed.
  Added CREATE FUNCTION parsing.
  DROP FUNCTION had to be partly merged with the old UDF code, because of the similar
  syntax.
  RETURN statement added, but still a no-op.

1 files changed, 12 insertions, 2 deletions

diff --git a/Docs/sp-implemented.txt b/Docs/sp-implemented.txt
index 97d4df2b62c..b3b12b7edb8 100644
--- a/Docs/sp-implemented.txt
+++ b/Docs/sp-implemented.txt
@@ -11,6 +11,8 @@ Summary of Not Yet Implemented:
   - SQL-99 COMMIT (related to BEGIN/END)
   - DECLARE CURSOR ...
   - FOR-loops (as it requires cursors)
+  - CASCADE/RESTRICT for ALTER and DROP
+  - ALTER/DROP METHOD (as it implies User Defined Types)
 
 
 Summary of what's implemented:
@@ -66,15 +68,23 @@ List of what's implemented:
       databases.)
 
 
-Open questions:
+Closed questions:
 
   - What is the expected result when creating a procedure with a name that
     already exists? An error or overwrite?
+  Answer: Error
+
   - Do PROCEDUREs and FUNCTIONs share namespace or not? I think not, but the
     we need to flag the type in the mysql.proc table and the name alone is
     not a unique key any more, or, we have separate tables.
     (Unfortunately, mysql.func is already taken. Use "sfunc" and maybe even
      rename "proc" into "sproc" while we still can, for consistency?)
+  Answer: Same tables, with an additional key-field for the type.
+
+
+Open questions:
+
   - SQL-99 variables and parameters are typed. For the present we don't do
     any type checking, since this is the way MySQL works. I still don't know
-    if we should keep it this way, or implement type checking.
+    if we should keep it this way, or implement type checking. Possibly we
+    should have optional, uset-settable, type checking.