12. The method of claim 1 , further comprising the steps of: repeating said selecting and identifying steps for each contract term in the purchasing contract, and generating a collection of contract-specific transaction data sets by marking, for each identified transaction data set having data elements matching the contract term criteria for all the contract terms in the contract, the identified transaction data set with a data element providing a contract code and a data element providing a contract term code.
1. A computer implemented method of generating an electronic database comprising a collection of transaction data sets that identify multiple independent transaction data sets to a single purchasing contract, said method comprising the steps of: creating a Transaction Detail Database for storing data sets representing transactions, including defining data storage adapted to storing the data sets in accordance with a common data format; collecting transaction data for each of a plurality of transactions from one or more sources; electronically storing, in the Transaction Detail Database, the collected transaction data as a transaction data set in accordance with the common data format; repeating the collecting and electronically storing steps multiple times to populate the Transaction Detail Database with a population of transaction data sets; selecting a contract term of a purchasing contract, from a Contract Registry Database storing a plurality of contract terms, wherein the contract term is associated in the Contract Registry Database with one or more contract term criteria defining the contract term; executing a computer program to identify a plurality of transaction data sets from the population of transaction data sets stored in the Transaction Detail Database with the contract term, including electronically comparing data elements of the transaction data sets with the contract term criteria; and generating a collection of contract-specific transaction data sets including each identified transaction data set; and wherein said step of executing a computer program to identify a plurality of transaction data sets with the contract term, includes: electronically comparing a data element of the transaction data sets with contract term customer criteria, electronically comparing a data element of the transaction data sets with contract term market criteria, electronically comparing a data element of the transaction data sets with contract term supplier criteria, and electronically comparing a data element of the transaction data sets with contract term product criteria.