First Find a sqli infected site .Now here i found a vulernable site
Now Let's start
Open havij and copy and paste infected link as shown in figureNow click in the "Analyze"
Then It shows some messages there....Be alert on it and be show patience for sometime to find it's vulernable and type of injection and if db server is mysql and it will find database name.Then after get it's database is name like xxxx_xxxx
Then Move to another operation to find tables by clicking "tables" as figure shown.Now click "Get tables" Then wait some time if needed
After founded the tables ,you can see there will be "users" Put mark on it and click in the " get columns " tab as shown in figureIn that Just put mark username and password and click "Get data"
Bingo Got now id and pass that may be admin...
The pass will get as md5 you can crack it also using this tool as shown in figure...