diff --git a/sql/bin/db-init b/sql/bin/db-init
index 95a1024d7..2f43c0b50 100755
--- a/sql/bin/db-init
+++ b/sql/bin/db-init
@@ -1,61 +1,69 @@
 #!/bin/bash
 set -e
 
 # Must be run as (a) Postgres super user
 
 SQL_INIT=swh-init.sql
 SQL_ENUMS=swh-enums.sql
 SQL_SCHEMA=swh-schema.sql
 SQL_FUNC=swh-func.sql
 SQL_INDEX=swh-indexes.sql
 SQL_TRIGGER=swh-triggers.sql
 SQL_DATA=swh-data.sql
 ROOT_SQLS="$SQL_INIT"
 USER_SQLS="$SQL_ENUMS $SQL_SCHEMA $SQL_FUNC $SQL_INDEX $SQL_TRIGGER $SQL_DATA"
 SQLS="$ROOT_SQLS $USER_SQLS"
 
 DB_ENCODING="UTF-8"
 DB_LOCALE="C.UTF-8"
 DB_TEMPLATE="template0"
 
+cd "$( dirname $0 )/.."
+
 if ! [ -f "$SQL_INIT" ] ; then
     echo "Cannot find $SQL_INIT. Abort."
-    echo "Note: db-init should usually be run from swh-storage/sql as bin/db-init."
     exit 2
 fi
 
-if [ -z "$1" -o -z "$2" -o -z "$3" ] ; then
-    echo "Usage: bin/db-init DB_PORT DB_NAME DB_USER"
-    echo "Example: bin/db-init 5432 softwareheritage-dev swhdev"
+if [ -z "$1" ] ; then
+    echo "Usage: bin/db-init DB_NAME [DB_USER [DB_PORT]]"
+    echo "Example: bin/db-init softwareheritage-dev"
     echo "Note: DB_NAME should not exist and will be created; DB_USER can exist."
     exit 2
 fi
-db_port="$1"
-db_name="$2"
-db_user="$3"
-conn_flags="--port ${db_port}"
+db_name="$1"
+db_user="${2:-$USER}"
+
+conn_flags=""
+if [ -n "$3" ]; then
+    conn_flags="--port $3"
+fi
 
-echo "I: creating Postgres user ${db_user} ..."
-createuser $conn_flags --pwprompt "$db_user" || true
+user_exists=$( psql postgres -tAc "SELECT 1 FROM pg_roles
+                                   WHERE rolname='$db_user'" )
+if [ "$user_exists" != "1" ]; then
+    echo "I: creating Postgres user ${db_user} ..."
+    createuser $conn_flags --pwprompt "$db_user" || true
+fi
 
 echo "I: creating Postgres database ${db_name} ..."
 createdb $conn_flags \
          --encoding "$DB_ENCODING" --locale "$DB_LOCALE" \
          --template "$DB_TEMPLATE" \
          --owner "$db_user" "$db_name"
 
 sqls_flags=''
 for f in $SQLS ; do
     sqls_flags="${sqls_flags} --file ${f}"
 done
 
 echo "I: initializing DB ${db_name} ..."
 psql $conn_flags ${sqls_flags} "$db_name"
 
 echo "I: granting privileges to user ${db_user} on DB ${db_name} ..."
 echo "grant all privileges on all tables in schema public to ${db_user}" | \
     psql $conn_flags "$db_name"
 echo "grant all privileges on all sequences in schema public to ${db_user}" | \
     psql $conn_flags "$db_name"
 
 echo "I: all done."