Hello. I have noticed that you are using 4 spaces as an indentation.
According to our codestyle, we use tab symbol, instead of spaces,
which is equal to 8 spaces.

Also, I don’t see any point in renaming function:
’sql_clear_stat_spaces’ -> ’sql_clear_stat_tables’.
I would even say that ‘spaces’ is more appropriate name,
since stat tables in fact are Tarantool’s system spaces.

> diff --git a/src/box/sql/build.c b/src/box/sql/build.c
> index 92f3cb6..7ca4191 100644
> --- a/src/box/sql/build.c
> +++ b/src/box/sql/build.c
> @@ -2128,19 +2128,33 @@ sqliteViewResetAll(sqlite3 * db)
>  /**
>   * Remove entries from the _sql_stat1 and _sql_stat4
>   * system spaces after a DROP INDEX or DROP TABLE command.
> - *
> - * @param pParse Parsing context.
> - * @param zType Type of entry to be deleted:
> - * 		'idx' or 'tbl' string literal.
> - * @param zName Name of index or table.
> + * 
> + * @param parse      The parsing context.
> + * @param table_name The table to be dropped or
> + *                   the table that contains index to be dropped.
> + * @param idx_name   Index to be dropped.
>   */
>  static void
> -sql_clear_stat_spaces(Parse * pParse, const char *zType, const char *zName)
> +sql_clear_stat_tables(Parse *parse, const char *table_name,
> +                      const char *idx_name)
>  {
> -	sqlite3NestedParse(pParse, "DELETE FROM \"_sql_stat1\" WHERE \"%s\"=%Q",
> -			   zType, zName);
> -	sqlite3NestedParse(pParse, "DELETE FROM \"_sql_stat4\" WHERE \"%s\"=%Q",
> -			   zType, zName);
> +    if (idx_name != NULL) {
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat1\" WHERE (\"idx\"=%Q AND "
> +                    "\"tbl\"=%Q)",
> +                    idx_name, table_name);
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat4\" WHERE (\"idx\"=%Q AND "
> +                    "\"tbl\"=%Q)",
> +                    idx_name, table_name);
> +    } else {
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat1\" WHERE \"tbl\"=%Q",
> +                    table_name);
> +        sqlite3NestedParse(parse,
> +                    "DELETE FROM \"_sql_stat4\" WHERE \"tbl\"=%Q",
> +                    table_name);
> +        }
>  }
> 
>