import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

import com.microsoft.sqlserver.jdbc.SQLServerDriver;

public class Main {

    private static final String JDBC_URL_TEMPLATE = "jdbc:sqlserver://mssql-2016.mw.lab.eng.bos.redhat.com;DatabaseName=%s";
    private static final String DATABASE_NAME_TEMPLATE = "dballo%02d";


    public static void main(String[] args) throws Exception {
        DriverManager.registerDriver(new SQLServerDriver());
        for (int i = 0; i < 30; i++) {
            String database = String.format(DATABASE_NAME_TEMPLATE, i);
            String user = database;
            String password = database;
            String jdbcUrl = String.format(JDBC_URL_TEMPLATE, database);
            try (Connection conn = DriverManager.getConnection(jdbcUrl, user, password)) {
                boolean before = isReadCommitedSnapshotOn(conn, database);
                if (!before)
                    enableReadCommitedSnapshot(conn);
                boolean after = isReadCommitedSnapshotOn(conn, database);
                System.out.println("Database: " + database + ", value: " + before + ", " + (before ? "not changed" : "changed to " + after));
            }
        }
    }

    private static boolean isReadCommitedSnapshotOn(Connection connection, String database) throws Exception {
        try (Statement stmt = connection.createStatement()) {
            try (ResultSet result = stmt.executeQuery("SELECT is_read_committed_snapshot_on FROM sys.databases WHERE name = '" + database + "'")) {
                result.next();
                return result.getBoolean(1);
            }
        }
    }

    private static void enableReadCommitedSnapshot(Connection connection) throws Exception {
        try (Statement stmt = connection.createStatement()) {
            stmt.execute("ALTER DATABASE CURRENT SET READ_COMMITTED_SNAPSHOT ON WITH ROLLBACK IMMEDIATE;");
        }
    }
}