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-rw-r--r--sql/sql_tvc.cc56
1 files changed, 55 insertions, 1 deletions
diff --git a/sql/sql_tvc.cc b/sql/sql_tvc.cc
index 816c6fe1089..b4538248e07 100644
--- a/sql/sql_tvc.cc
+++ b/sql/sql_tvc.cc
@@ -796,6 +796,38 @@ bool Item_subselect::wrap_tvc_into_select(THD *thd, st_select_lex *tvc_sl)
}
+/*
+ @brief
+ Check whether the items are of comparable type or not
+
+ @details
+ This check are done because materialization is not performed
+ if the left expr and right expr are of the same types.
+ @see subquery_types_allow_materialization()
+
+ @retval
+ 0 comparable
+ 1 not comparable
+*/
+
+static bool cmp_row_types(Item* item1, Item* item2)
+{
+ uint n= item1->cols();
+ if (item2->check_cols(n))
+ return true;
+
+ for (uint i=0; i < n; i++)
+ {
+ Item *inner= item1->element_index(i);
+ Item *outer= item2->element_index(i);
+ if (!inner->type_handler()->subquery_type_allows_materialization(inner,
+ outer))
+ return true;
+ }
+ return false;
+}
+
+
/**
@brief
Transform IN predicate into IN subquery
@@ -840,10 +872,22 @@ Item *Item_func_in::in_predicate_to_in_subs_transformer(THD *thd,
/* SELECT_LEX object where the transformation is performed */
SELECT_LEX *parent_select= lex->current_select;
uint8 save_derived_tables= lex->derived_tables;
+
+ /*
+ Make sure that create_tmp_table will not fail due to too long keys.
+ Here the strategy would mainly use materialization, so we need to make
+ sure that the materialized table can be created.
+
+ The checks here are the same as in subquery_type_allows_materialization()
+ */
+ uint32 length= max_length_of_left_expr();
+ if (!length || length > tmp_table_max_key_length() ||
+ args[0]->cols() > tmp_table_max_key_parts())
+ return this;
for (uint i=1; i < arg_count; i++)
{
- if (!args[i]->const_item())
+ if (!args[i]->const_item() || cmp_row_types(args[0], args[i]))
return this;
}
@@ -948,6 +992,16 @@ err:
}
+uint32 Item_func_in::max_length_of_left_expr()
+{
+ uint n= args[0]->cols();
+ uint32 length= 0;
+ for (uint i=0; i < n; i++)
+ length+= args[0]->element_index(i)->max_length;
+ return length;
+}
+
+
/**
@brief
Check if this IN-predicate can be transformed in IN-subquery