3. A computer-readable storage medium containing a program which, when executed by a processor, performs an operation for generating a reusable query component, the operation comprising: for each of a plurality of reusable query components: (i) receiving, from a user, one or more query conditions to associate with a reusable query component, wherein each condition provides a portion of a database query in a query language, wherein the condition operates to filter results to be returned by the database query, wherein each are condition is an abstract query condition defined by one or more logical fields and wherein each condition includes: a field name referencing a field in a database, a comparison operator, and a comparison value to which one or more database values for the field are compared, based on the comparison operator, to determine whether the condition is satisfied for a given database value corresponding to the field; (ii) receiving, from the user, a name for the reusable query component; and (iii) receiving, from the user, an access level to assign to the reusable query component, wherein the access level indicates a privilege level required for a user in order for the reusable query component to be made available to the user for use in building in a database query, and wherein the access level is specific to the reusable query component; (iv) associating the one or more query conditions with the specified name and the specified access level; and (v) storing the one or more query conditions, the specified name, and the specified access level; wherein the storing comprises storing XML representations of the one or more query conditions, the specified access level, and the specified name in a database for later retrieval; receiving a request to include at least two of the plurality of reusable query component in abstract query, wherein the request specifies the respective name of the at least two reusable query components; and upon determining that the request satisfies the respective specified access level for the reusable query components, including all of the respective query conditions of the reusable query components in the abstract query, responsive to the request.
3. A computer-readable storage medium containing a program which, when executed by a processor, performs an operation for generating a reusable query component, the operation comprising: for each of a plurality of reusable query components: (i) receiving, from a user, one or more query conditions to associate with a reusable query component, wherein each condition provides a portion of a database query in a query language, wherein the condition operates to filter results to be returned by the database query, wherein each are condition is an abstract query condition defined by one or more logical fields and wherein each condition includes: a field name referencing a field in a database, a comparison operator, and a comparison value to which one or more database values for the field are compared, based on the comparison operator, to determine whether the condition is satisfied for a given database value corresponding to the field; (ii) receiving, from the user, a name for the reusable query component; and (iii) receiving, from the user, an access level to assign to the reusable query component, wherein the access level indicates a privilege level required for a user in order for the reusable query component to be made available to the user for use in building in a database query, and wherein the access level is specific to the reusable query component; (iv) associating the one or more query conditions with the specified name and the specified access level; and (v) storing the one or more query conditions, the specified name, and the specified access level; wherein the storing comprises storing XML representations of the one or more query conditions, the specified access level, and the specified name in a database for later retrieval; receiving a request to include at least two of the plurality of reusable query component in abstract query, wherein the request specifies the respective name of the at least two reusable query components; and upon determining that the request satisfies the respective specified access level for the reusable query components, including all of the respective query conditions of the reusable query components in the abstract query, responsive to the request. 7. The computer-readable storage medium of claim 3 , wherein the operations further comprise mapping the one or more logical fields to physical entities of data in the database.