Revision history [back]

The procedure for executing a PostgreSQL query with multiple parameters of diverse values can vary depending on how you are interacting with the database. Here are a few possible ways to do it:

1. Using psql: If you are using the psql command-line tool, you can use the following syntax to execute a query with multiple parameters:

psql mydatabase -c "SELECT * FROM mytable WHERE column1 = $1 AND column2 = $2" --param1=value1 --param2=value2

This will substitute the values of value1 and value2 for the placeholders $1 and $2 in the query. You can provide as many parameters as you need, separated by spaces after the query text.

1. Using psycopg2 (Python): If you are using the psycopg2 library in Python, you can use parameterized queries to provide multiple parameters of diverse values. Here is an example:

import psycopg2

conn = psycopg2.connect(database="mydatabase", user="myuser", password="mypassword", host="localhost", port="5432")

cursor = conn.cursor()

query = "SELECT * FROM mytable WHERE column1 = %s AND column2 = %s"
params = (value1, value2)
cursor.execute(query, params)

rows = cursor.fetchall()

conn.close()

In this example, the %s placeholders in the query text are replaced by the values in the params tuple. You can use as many placeholders and parameters as you need.

1. Using JDBC (Java): If you are using JDBC in Java, you can use prepared statements to execute a query with multiple parameters. Here is an example:

import java.sql.*;

Connection conn = DriverManager.getConnection("jdbc:postgresql://localhost/mydatabase", "myuser", "mypassword");

String query = "SELECT * FROM mytable WHERE column1 = ? AND column2 = ?";
PreparedStatement pstmt = conn.prepareStatement(query);
pstmt.setString(1, value1);
pstmt.setString(2, value2);

ResultSet rs = pstmt.executeQuery();

conn.close();

In this example, the ? placeholders in the query text are replaced by calls to the setString method on the prepared statement. You can use as many placeholders and parameters as you need, and you can use different types of setters depending on the data types of your parameters.