Check table existence method

Question

I have the following Java method that is suppose to determine whether a given table exists or not:
public boolean tableExists(String table) {
String defstmt = "select TABLE_NAME from ALL_TABLES where (TABLE_NAME = '" + table + "')";
System.err.println("tableExists: stmt = " + defstmt);
tc.executeSEL(defstmt);
ResultSet rs = tc.getRS();
String tname = new String();
try {
while (rs.next()) {
rs.getString(tname);
System.err.println("tableExists.try: tname = " + tname);
rs.close();
return true;
catch (SQLException ex) {
System.err.println("tableExists.catch: tname not found");
try {
rs.close();
catch (SQLException ex1) {
return false;
Since this one didn't appear to work reliabily a friend suggested the following:
public boolean tableExists(String table) {
boolean exists = false;
String defstmt = "select TABLE_NAME from ALL_TABLES where (TABLE_NAME = '" + table + "')";
System.err.println("tableExists: stmt = " + defstmt);
if (tc.executeSEL(defstmt)) {
ResultSet rs = tc.getRS();
try {
exists = rs.first();
// This returns false if the rs is empty
// This should be sufficient if the query will return zero rows or one row.
// If there's a possibility that the query could return more than one row
// (for example if multiple schema data is in there and a table name
// might be duplicated), then this section will need to be more picky.
System.err.println("tableExists.try: tname found");
catch (SQLException ex) {
System.err.println("tableExists.catch: tname not found");
try {
rs.close();
catch (SQLException ex1) {
return exists;
Bottom line; neither method seems to be able to determine whether the table exists. Someone out there got any suggestions?
Thanks in advance
RCulp

Answer 1

The method "tc.executeSEL" is in a class "TableConnector" which I use to hold connection data and execute SQL statements. A new instance of the "TableConnector" class is created for each table prior to the check for existence. The method itself is boolean, returning true or false if the SQL runs successfully:
public boolean executeSEL(String inpstmt) {
rs = null;
try {
Connection conn = ConnectionData.getConnectionData().openConnection();
stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
rs = stmt.executeQuery(inpstmt);
return true;
//debugdumpRS(rs);
catch (SQLException ex) {
System.err.println("SEL Statement = " + inpstmt);
System.err.println("Error code = " + ex.getErrorCode());
System.err.println("Error message = " + ex.getMessage());
System.err.println("SQL state = " + ex.getSQLState());
return false;
/*FINALLY CAN NOT BE USED HERE; ERASES THE RESULT SET
finally {
if (stmt != null) {
try {
stmt.close();
catch (SQLException ex) {
System.err.println("Error code = " + ex.getErrorCode());
System.err.println("Error message = " + ex.getMessage());
The TableConnector class also has a get method for the ResultSet:
public ResultSet getRS() {
return rs;
I'll try your suggestion and post the result.
Thanks
RCulp