reference.md

Database Interaction

1. Create a database connection

   • Test if connection succeeded (recommended)

2. Perform database query

   • Test if query succeeded (recommended)

3. Use returned data (if any)

4. Release returned data

5. Close database connection

PHP mysqli Functions

Complete function definitions are available at https://php.net

Procedural Style	Object-Oriented Style
mysqli_affected_rows($mysqli)	$mysqli->affected_rows
mysqli_close($mysqli)	$mysqli->close()
mysqli_connect_errno($mysqli)	$mysqli->connect_errno
mysqli_connect_error($mysqli)	$mysqli->connect_error
mysqli_connect(...)	new mysqli(...)
mysqli_insert_id($mysqli)	$mysqli->insert_id
mysqli_query($mysqli, $string)	$mysqli->query($string)
mysqli_real_escape_string($mysqli, $string)	$mysqli->real_escape_string($string)
mysqli_fetch_array($result)	$result->fetch_array()
mysqli_fetch_assoc($result)	$result->fetch_assoc()
mysqli_fetch_object($result)	$result->fetch_object()
mysqli_fetch_row($result)	$result->fetch_row()
mysqli_free_result($result)	$result->free()
mysqli_num_rows($result)	$result->num_rows

Example SQL Statements

SELECT * FROM table_name
WHERE column1 = 'beep'
AND column2 = 'bam'
ORDER BY column3 ASC
LIMIT 20;

INSERT INTO table_name (column1, column2, column3)
VALUES ('beep', 'bam', 'boop');

UPDATE table_name
SET column1='beep', column2='bam', column3='boop';

DELETE FROM table_name
WHERE column1='beep' LIMIT 1;