Hi Anurag, Before starting this hope you have created a table and inserted data. In HBase insert is done using put.
So for tracking the read flow in HBase it is get data from table There are two things -> Get entire table contents -> get a specific row. For getting a specific row using a java client. You need to set the row in the Get object. Call table.get(Get g). The flow goes into HTable get method. A remote call is made to Region Server get() method. From here it gets the region info and goes to the specific region. Finds if any store files are present. If so scans the store files and if present in memstore scans the memstore and return you the result. For scanning the entire table create a scan object, call table.getScanner(scan). You can see a client scanner getting used which makes a call to the all the RS that has the regions of the table and returns you the result. Further you can also you filters. Hope am clear. Regards Ram -----Original Message----- From: Anurag Awasthi [mailto:[email protected]] Sent: Thursday, August 11, 2011 3:38 PM To: [email protected] Subject: Finding the trace of a query Hi, I am relatively new to HBase and I am trying to find the path that is followed (i.e. the lines executed in the source code) in a query, say "select *" . Can anyone help me in this regard. Thanks
