This might not be a question but a technical memo for future reference
Deleted records query command (example):
SELECT Count() FROM Contact WHERE IsDeleted = true ALL ROWS SELECT Id, LastName, IsDeleted FROM Contact WHERE IsDeleted = true ALL ROWS
Query editor of the developer console does not support "ALL ROWS" keyword thus it does not support deleted records query.
But, the same commands work fine in Developer console's Anonymous Execution
Integer deletedContacts = [ SELECT COUNT() FROM Contact WHERE IsDeleted = true ALL ROWS ]; System.debug(deletedContacts);
And the result