Inspect Oracle Database Schema and Tables with Kotlin

// Filename: conn.kts
// Usage: kotlinc -cp /home/zedeng/Downloads/ojdbc7.jar -script conn.kts

import java.sql.*

Class.forName("oracle.jdbc.driver.OracleDriver")
val conn = DriverManager.getConnection("jdbc:oracle:thin:@myremotehost:1521:MYDB", "system", "mypassword123")

println("Database connection established $conn")
println("Database Default Catalog: ${conn.getCatalog()}")
println("Database Default Schema: ${conn.getSchema()}")

val m = conn.getMetaData()
println("${m.getDatabaseProductName()} ${m.getDatabaseMajorVersion()} ${m.getDatabaseMinorVersion()}")

println("List of Schemas")
var rs: ResultSet
rs = m.getSchemas()
while(rs.next()) {
    println("  ${rs.getObject(1)}")
}
rs.close()

val listSchemaName = conn.getSchema()
println("List of Tables for ${listSchemaName}")
rs = m.getTables(conn.getCatalog(), listSchemaName, null, null)
while(rs.next()) {
    val name = rs.getObject("TABLE_NAME")
    println("  $name")
}
rs.close()

println("Execute query:")
val stmt = conn.createStatement()
rs = stmt.executeQuery("SELECT 1+1 FROM DUAL")
while(rs.next()) {
    val v = rs.getObject(1)
    println("  1 + 1 from DB=$v")
}
rs.close()
stmt.close()

conn.close()