Section 29(2)(a) in Rajasthan Transparency in Public Procurement Rules, 2013
(a)A procuring entity may award a rate contract by the method of open competitive bidding. If it is not possible to adopt the method of open competitive bidding, the procuring entity after recording reasons may adopt another method of procurement. An approximate quantity of required goods, works or service during the period shall be indicated in the Notice Inviting Bids, but no minimum quantity is guaranteed.