Metadata is data about data. E.g. if in data mart we are receiving any file. Then metadata will contain information like how many columns, file is fix width/limited, ordering of fields, data types of field etc.
metadata is data about data..it contains information about the cardinality etc..cardinality is nothing but number of attributes
Metedata in DWH is similar to data dictonary in DBMS.Metadata plays a key role in converting raw data into knowledge,as it helps to provide valuable description about the data.So that,it can be understand and converted into meaningful information.
Metadata is structured information that describes, explains, locates, or otherwise makes it easier to retrieve, use, or manage an information resource. Metadata is often called data about data or information about information.
Meta data is data about data and contains the location and description of warehouse system components; names, definition, structure and content of the data warehouse and end user views; identification of authoritative data sources (system of record); integration and transformation of rules used to populate the data warehouse; a history of warehouse updates and refreshments; metrics used to analyze warehouse performance vis-a-vis end-user usage
------METADATA------ It is the data which describes the properties or characteristics of end users data and the context of data. Metadata properties can include info such as: -data name -definitions -length or size -values allowed -source of data -ownership Metadata and ddata are always seprate. Metadata enables the database designers and programmers to understand exactly in which from the data should exist with in the system