I got it ,
Alfresco create all the Model as a node,
so when u create User , Folder , Document , Image , Space etc… then alfresco store these as a node and placed the entry in alf_node table .
All The properties of node are placed in the alf_node_properties table . In alf_node_properties table you will find string_value and qname_id columns. The qname_id define entry in alf_qname table. By qname_id you can check that your string_value belongs to which local_name .