diff --git a/README.org b/README.org
index 3e208f7..767a421 100644
--- a/README.org
+++ b/README.org
@@ -37,5 +37,17 @@
 
   #+END_SRC
 
+** Build codeql database
+   #+BEGIN_SRC sh
+     # Build the db with source commit id.
+     export PATH=$HOME/local/vmsync/codeql224:"$PATH"
+     SRCDIR=$HOME/local/codeql-dataflow-sql-injection/
+     DB=$HOME/local/db/codeql-dataflow-sql-injection-$(cd $SRCDIR && git rev-parse --short HEAD)
 
+     echo $DB
+     test -d "$DB" && rm -fR "$DB"
+     mkdir -p "$DB"
 
+     cd $SRCDIR
+     codeql database create --language=cpp -s $SRCDIR  -j 8 -v $DB --command='./build.sh'
+   #+END_SRC