Discover.java

import java.sql.*;
import java.util.Properties;

public class Discover {
    public static void main(String[] args) throws Exception {
        Properties props = new Properties();
        props.setProperty("user", "ovr");
        props.setProperty("password", "test");
        try (Connection conn = DriverManager.getConnection("jdbc:postgresql://localhost:5555/db", props)) {
            // List public tables
            ResultSet tables = conn.getMetaData().getTables(null, "public", "%", null);
            System.out.println("=== PUBLIC TABLES ===");
            while (tables.next()) {
                System.out.println("  " + tables.getString("TABLE_NAME") + " (" + tables.getString("TABLE_TYPE") + ")");
            }

            // For each table, list columns
            Statement st = conn.createStatement();
            ResultSet rs = st.executeQuery(
                "SELECT table_name, column_name, data_type FROM information_schema.columns WHERE table_schema = 'public' ORDER BY table_name, ordinal_position");
            System.out.println("\n=== COLUMNS ===");
            while (rs.next()) {
                System.out.printf("  %s.%s  (%s)%n", rs.getString(1), rs.getString(2), rs.getString(3));
            }
        }
    }
}

PgReproducer.java

import java.sql.*;
import java.util.Properties;

/**
 * Reproducer for CubeSQL per-column format bug (GitHub issue #10418).
 *
 * Tableau and other JDBC clients use the Extended Query protocol which
 * requests binary format for specific column types (int8, float8) and
 * text format for others.  This mix of per-column format codes in the
 * Bind message exposes a bug in CubeSQL where RowDescription only sends
 * a single format code instead of per-column format codes.
 *
 * Usage:
 *   cd rust/cubesql/java-reproducer
 *   curl -O https://jdbc.postgresql.org/download/postgresql-42.7.5.jar
 *   javac PgReproducer.java
 *   java -cp .:postgresql-42.7.5.jar PgReproducer
 */
public class PgReproducer {

    public static void main(String[] args) {
        String url = "jdbc:postgresql://localhost:5555/db";
        Properties props = new Properties();
        props.setProperty("user", "ovr");
        props.setProperty("password", "test");
        // After 1 execution the driver switches to server-prepared → binary transfer
        props.setProperty("prepareThreshold", "1");
        // Enable binary transfer only for int8 (OID 20) and float8 (OID 701)
        // This creates a MIX of binary and text format codes in the Bind message,
        // just like Tableau does.
        props.setProperty("binaryTransfer", "true");
        props.setProperty("binaryTransferEnable", "20,701");
        props.setProperty("binaryTransferDisable", "");

        System.out.println("Connecting to " + url + " ...");

        try (Connection conn = DriverManager.getConnection(url, props)) {
            System.out.println("Connected.  Server version: "
                    + conn.getMetaData().getDatabaseProductVersion());

            // Query 1: orders without aggregation — mixed types
            // id=float8(binary), status=text(text), order_sum=float8(binary), created=timestamp(text)
            runQuery(conn, "Query 1: orders without SUM",
                    "SELECT id, status, order_sum, created FROM orders LIMIT 5");

            // Query 2: orders with SUM aggregation — mixed types
            // status=text(text), total=float8(binary), cnt=int8(binary)
            runQuery(conn, "Query 2: orders with SUM",
                    "SELECT status, SUM(order_sum) AS total, COUNT(*) AS cnt FROM orders GROUP BY 1");

            System.out.println("\nALL QUERIES SUCCEEDED — no errors.");
        } catch (Exception e) {
            System.err.println("\nFAILED:");
            e.printStackTrace();
            System.exit(1);
        }
    }

    private static void runQuery(Connection conn, String label, String query) throws SQLException {
        System.out.println("\n=== " + label + " ===");
        System.out.println("SQL: " + query);

        // Reuse the same PreparedStatement so the driver crosses prepareThreshold
        // and switches to binary format on the 2nd+ execution.
        try (PreparedStatement ps = conn.prepareStatement(query)) {
            for (int attempt = 1; attempt <= 3; attempt++) {
                System.out.println("\n  --- Execution #" + attempt
                        + (attempt == 1 ? " (text format)" : " (mixed binary/text format)") + " ---");
                try (ResultSet rs = ps.executeQuery()) {
                    ResultSetMetaData meta = rs.getMetaData();
                    int cols = meta.getColumnCount();

                    System.out.println("  Columns (" + cols + "):");
                    for (int i = 1; i <= cols; i++) {
                        System.out.printf("    [%d] %s  type=%s (%d)%n",
                                i,
                                meta.getColumnLabel(i),
                                meta.getColumnTypeName(i),
                                meta.getColumnType(i));
                    }

                    System.out.println("  Rows:");
                    int rowNum = 0;
                    while (rs.next()) {
                        rowNum++;
                        StringBuilder sb = new StringBuilder("    row " + rowNum + ": ");
                        for (int i = 1; i <= cols; i++) {
                            if (i > 1) sb.append(", ");
                            Object val = rs.getObject(i);
                            sb.append(meta.getColumnLabel(i))
                              .append("=")
                              .append(val)
                              .append(" (")
                              .append(val == null ? "null" : val.getClass().getSimpleName())
                              .append(")");
                        }
                        System.out.println(sb);
                    }
                    System.out.println("  Total rows: " + rowNum);
                } catch (SQLException e) {
                    System.err.println("  ERROR on execution #" + attempt + ": " + e.getMessage());
                    throw e;
                }
            }
        }
    }
}