DynamoDB condition operator - suguanyu/WechatTinyProgram GitHub Wiki
http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_Condition.html
Represents the selection criteria for a Query or Scan operation:
For a Query operation, Condition is used for specifying the KeyConditions to use when querying a table or an index. For KeyConditions, only the following comparison operators are supported: EQ | LE | LT | GE | GT | BEGINS_WITH | BETWEEN Condition is also used in a QueryFilter, which evaluates the query results and returns only the desired values. For a Scan operation, Condition is used in a ScanFilter, which evaluates the scan results and returns only the desired values.