1. A method for obtaining information about a data storage system, comprising: receiving a request for information from a data storage application; executing, in response to the request, a compiled software construct to retrieve from a database a set of metrics indicative of performance of the data storage system, the compiled software construct including a database language instruction, the database language instruction including a reference to a data inquiry definition stored in an uncompiled file external to the compiled software construct; sending the database language instruction, including the data inquiry definition, to the database, to execute the database language instruction on the database and produce a result; receiving the result of the database language instruction by the compiled software construct; and returning the information to the data storage application based on the result of the database language instruction, wherein a first field of the database stores metric values of the data storage system and a second field of the database stores time values indicating when respective metric values stored in the first field of the database were obtained, wherein the data inquiry definition in the uncompiled file includes an arithmetic operation to be applied between a first record and a second record of the database, the first record and the second record of the database each including a value for the first field and a value the second field, and wherein the arithmetic operation includes: subtracting a value of the first field in the first record from a value of the first field in the second record to calculate a metric difference value, subtracting a time value in the second field of the first record from a time value in the second field of the second record to calculate a time difference; and dividing the metric difference value by the time difference to calculate a metric rate of change.