Hi, Aleksey, Despite the email subject, this is a combined diff of three commits, git diff 071c20fd23b2 2fecd944d6dc On Apr 04, Aleksey Midenkov wrote:

diff --git a/sql/field.cc b/sql/field.cc index 8b96c473ab6..d6be66cf399 100644 --- a/sql/field.cc +++ b/sql/field.cc @@ -2516,7 +2521,7 @@ Field *Field::new_key_field(MEM_ROOT *root, TABLE *new_table, uchar *new_null_ptr, uint new_null_bit) { Field *tmp; - if ((tmp= make_new_field(root, new_table, table == new_table))) + if ((tmp= make_new_field({root, new_table, table == new_table})))

it's a creative trick, I admit, but let's not do it. looks very weird, we don't have it anywhere else. it's not needed either, because you don't need to pass down a new argument, see below

{ tmp->ptr= new_ptr; tmp->null_ptr= new_null_ptr; @@ -8278,12 +8281,28 @@ int Field_varstring::cmp_binary(const uchar *a_ptr, const uchar *b_ptr, }

-Field *Field_varstring::make_new_field(MEM_ROOT *root, TABLE *new_table, - bool keep_type) +Field *Field_varstring::make_new_field(make_new_field_args args) { - Field_varstring *res= (Field_varstring*) Field::make_new_field(root, - new_table, - keep_type); + Field_varstring *res= (Field_varstring*) Field::make_new_field(args); + if (res) + res->length_bytes= length_bytes; + return res; +} + + +Field *Field_varstring_compressed::make_new_field(make_new_field_args args) +{ + Field_varstring *res; + if (args.tmp_field)

tmp field is a field of a tmp table. Unfortunately, INTERNAL_TMP_TABLE value of new_table->s->tmp_table is very overloaded and no longer means internal temporary table anymore. I think we'll need to fix it someday. But a smaller fix for today could be, like @@ -1113,6 +1113,11 @@ struct TABLE_SHARE return (tmp_table == SYSTEM_TMP_TABLE) ? 0 : table_map_id; } + bool is_optimizer_tmp_table() + { + return tmp_table == INTERNAL_TMP_TABLE && !db.length && table_name.length; + } + using the fact that optimizer tmp tables are all named "(temporary)" or something like that and have no db. Using this one can do a fix, like @@ -8281,11 +8279,23 @@ int Field_varstring::cmp_binary(const uchar *a_ptr, con> Field *Field_varstring::make_new_field(MEM_ROOT *root, TABLE *new_table, bool keep_type) { - Field_varstring *res= (Field_varstring*) Field::make_new_field(root, + Field_varstring *res; + if (new_table->s->optimizer_tmp_table()) + { + res= new (root) Field_varstring(ptr, field_length, length_bytes, null_ptr, + null_bit, Field::NONE, &field_name, + new_table->s, charset()); + if (res) + res->init_for_make_new_field(new_table, orig_table); + } + else + { + res= (Field_varstring*) Field::make_new_field(root, new_table, keep_type); if (res) res->length_bytes= length_bytes; + } return res; }

+ { + /* Compressed fields can't have keys (see Field_varstring_compressed::key_cmp()). */ + res= new (args.root) Field_varstring(*this); + res->init_new_field(args); + /* See Column_definition::create_length_to_internal_length_string() */ + res->field_length--; + } + else + res= (Field_varstring*) Field::make_new_field(args); if (res) res->length_bytes= length_bytes; return res;

Regards, Sergei Chief Architect, MariaDB Server and security@mariadb.org