How to enable tempalte and block path hints in Magento

Run this query in your database.

INSERT INTO core_config_data (scope, scope_id, path,value)

VALUES ('default', 0, 'dev/debug/template_hints', 1),
('default', 0, 'dev/debug/template_hints_blocks', 1);

To disable them again, run this query:
UPDATE core_config_data set value = 0 where scope = 'default' and scope_id = 0 and path ='dev/debug/template_hints'

To enable again run this query:
UPDATE core_config_data set value = 1 where scope = 'default' and scope_id = 0 and path ='dev/debug/template_hints'