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copied!<p>This is a check I used to (re)create the H2 database:</p> <pre><code>// IMPORTANT A sorted list of table names. private static final String[] REQUIRED_TABLES = { "USER", ... }; public static final String CREATE_USER = "create table USER (...)"; private boolean schemaExists() throws SQLException { final List<String> requiredTables = Arrays.asList(REQUIRED_TABLES); final List<String> tableNames = new ArrayList<String>(); final Connection conn = dataSource.getConnection(); try { final Statement st = conn.createStatement(); final ResultSet rs = st.executeQuery("show tables"); while (rs.next()) { tableNames.add(rs.getString("TABLE_NAME")); } rs.close(); st.close(); } finally { if (conn != null) { conn.close(); } } Collections.sort(tableNames); return tableNames.equals(requiredTables); } private void initializeDatabase() throws SQLException { final Connection conn = dataSource.getConnection(); try { if (schemaExists()) { return; } final Statement st = conn.createStatement(); st.executeUpdate(CREATE_USER); conn.commit(); } finally { if (conn != null) { conn.close(); } } } </code></pre> <p>And you just call:</p> <pre><code> initializeDatabase(); </code></pre> <p>Notice the list of required tables has to be sorted because I use <code>List.equals()</code> to compare two lists. It would probably be better to also programmatically sort the required tables list too.</p> <p>It's not fool-proof (not checking if any table exists and if it should be altered) but it works for me.</p> <p>Take a look at the <a href="http://www.h2database.com/html/grammar.html#show" rel="nofollow">SHOW</a> command for other uses.</p>

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