#475: Improve error message for unsupported named parameters

dbdimp.c

@@ -4209,6 +4209,23 @@ int dbd_bind_ph(SV *sth, imp_sth_t *imp_sth, SV *param, SV *value,
 
   if (param_num <= 0  ||  param_num > DBIc_NUM_PARAMS(imp_sth))
   {
+    if (!looks_like_number(param))
+    {
+      STRLEN len;
+      char *paramstring;
+      paramstring = SvPV(param, len);
+      if(paramstring[len] == 0 && strlen(paramstring) == len)
+      {
+        do_error(sth, JW_ERR_ILLEGAL_PARAM_NUM, form("named parameters are unsupported: %s", paramstring), NULL);
+        return FALSE;
+      }
+      else
+      {
+        do_error(sth, JW_ERR_ILLEGAL_PARAM_NUM, "<param> could not be coerced to a C string", NULL);
+        return FALSE;
+      }
+    }
+
     do_error(sth, JW_ERR_ILLEGAL_PARAM_NUM, "Illegal parameter number", NULL);
     return FALSE;
   }

lib/DBD/mysql.pm

@@ -1725,6 +1725,10 @@ parameter value and C<execute> the statement again, with other values
 unchanged. The attribute remains properly populated after the C<finish> 
 method is called, with the values from the last execution.
 
+MySQL does not support named place holders in C<bind_param>.  If a
+string is passed to C<bind_param> as the parameter index then a
+"named parameters are unsupported" error is reported.
+
 =item mysql_gtids
 
 Returns GTID(s) if GTID session tracking is ensabled in the server via

t/45bindnamedparam_error.t

@@ -0,0 +1,53 @@
+use strict;
+use warnings;
+
+use Test::More;
+use DBI;
+use vars qw($test_dsn $test_user $test_password);
+use lib 't', '.';
+require 'lib.pl';
+
+my $dbh;
+eval {$dbh = DBI->connect($test_dsn, $test_user, $test_password,
+  { RaiseError => 1, AutoCommit => 1}) or ServerError();};
+
+if ($@) {
+    plan skip_all => "no database connection";
+}
+plan tests => 11;
+
+SKIP: {
+    skip 'SET @@auto_increment_offset needs MySQL >= 5.0.2', 2 unless $dbh->{mysql_serverversion} >= 50002;
+    ok $dbh->do('SET @@auto_increment_offset = 1');
+    ok $dbh->do('SET @@auto_increment_increment = 1');
+}
+
+my $create= <<EOT;
+CREATE TEMPORARY TABLE dbd_mysql_t45bindnamedparam (
+    id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
+    num INT(3))
+EOT
+
+ok $dbh->do($create), "create table dbd_mysql_t45bindnamedparam";
+
+ok $dbh->do("INSERT INTO dbd_mysql_t45bindnamedparam VALUES(NULL, 1)"), "insert into dbd_mysql_t45bindnamedparam (null, 1)";
+
+my $rows;
+ok ($rows= $dbh->selectall_arrayref("SELECT * FROM dbd_mysql_t45bindnamedparam"));
+
+is $rows->[0][1], 1, "\$rows->[0][1] == 1";
+
+ok (my $sth = $dbh->prepare("SELECT * FROM dbd_mysql_t45bindnamedparam WHERE num = :num"));
+
+$dbh->{PrintError} = 0;
+$dbh->{PrintWarn} = 0;
+eval {($sth->bind_param(":num", 1, SQL_INTEGER()));};
+$dbh->{PrintError} = 1;
+$dbh->{PrintWarn} = 1;
+ok defined($DBI::errstr);
+
+like($DBI::errstr, qr/named parameters are unsupported/, 'bind_param reports exepcted error with named parameter');
+
+ok ($sth->finish());
+
+ok ($dbh->disconnect());