1. A method for persisting data received from different data sources, the method comprising: receiving, at a data aggregation server, data from a plurality of data sources having a plurality of schemas, the data including a plurality of data fields, and at least two of the data fields being structured according to different schema of the plurality of schema; aggregating a subset of the plurality of data fields that are relevant to an object stored by the data aggregation server; generating a record identifier associated with the object; generating a different insert event associated with each data field of the aggregated subset of data fields, each insert event including a value corresponding to the associated data field; storing each insert event in a different row of an operation log, each row including the record identifier, a field name corresponding to the data field associated with the insert event stored in the row, the value corresponding to the data field, and a timestamp of when the insert event occurred; receiving, from a client device, a first data request for accessing a value corresponding to a data field of the aggregated subset of data fields; transmitting, to the client device, the value included in the identified row in response to the first data request; generating a modify event in a new row of the operation log, the new row including the record identifier, the field name corresponding to the data field associated with the modified value, a modified value, and a timestamp of when the modify event occurred; identifying a row in the operation log that stores a most recent event associated with the data field corresponding to the modified value; and responsive to identifying the row associated with the modify event as the most recent event, transmitting, to the client device, the modified value.