feat(postgres_java): add class LctMsgHasLct.java

This commit is contained in:
dancingCycle 2022-05-10 15:14:40 +02:00
parent e488cf0f03
commit 447d90a7d4
1 changed files with 38 additions and 0 deletions

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package de.swingbe.postgres_java;
import java.sql.*;
import java.util.logging.Level;
import java.util.logging.Logger;
public class LctMsgHasLct {
public static void main(String[] args) {
//connection URL for the postgres database
//jdbc:postgresql://<host>:<port>/<database name>
String url = "jdbc:postgresql://localhost:5432/testdb";
String user = "usr";
String password = "#password";
//get all columns from a table
String date = "2022-05-10";
String trip = "4457006";
String query = "SELECT " + "CASE WHEN EXISTS " + "(" + "SELECT * from lct_msg_y where vc_date='" + date + "' AND vc_trip='" + trip + "')" + "THEN 'true'" + "ELSE 'false'" + "END;";
//create prepared statement using placeholders instead of directly writing values
try (Connection con = DriverManager.getConnection(url, user, password); PreparedStatement pst = con.prepareStatement(query); ResultSet rs = pst.executeQuery()) {
//advance cursor to the next record
//return false if there are no more records in the result set
while (rs.next()) {
System.out.println("" + rs.getString(1));
}
} catch (SQLException ex) {
Logger lgr = Logger.getLogger(LctMsgHasLct.class.getName());
lgr.log(Level.SEVERE, ex.getMessage(), ex);
}
}
}