MySQLi PHP Syntax – Working with Data

1. CN5109
WEB APPLICATION
DEVELOPMENT
Chapter 8
MySQLi PHP Syntax – Working with Data

2. MySQLi Insert Data
• To insert data into MySQLi table, you would need to use
SQL INSERT INTO command.
• You can use INSERT INTO command into PHP function
mysqli_query() to insert data into a MySQLi table.

3. MySQLi Insert Data
• Example:
/* HTML FORM*/
<form action = “ " method = "post">
<label>Full Name :</label>
<input type = "text" name = “fname" /> <br /> <br />
<input type = "submit" value ="Submit" name = "submit"/> <br />
</form>

4. MySQLi Insert Data
• Example:
/* PHP FILE */
<?php
// Connection to Database
// Select Database
$sql = "INSERT INTO table1(fname)VALUES ('".$_POST[“fname"]."')";
if (mysqli_query($conn, $sql))
{
echo "New record created successfully";
}
else
{
echo "Error: " . $sql . “ " . mysqli_error($conn);
}
mysqli_close($conn);
?>

5. MySQLi Query Data
• The SQL SELECT command is used to fetch data from
MySQLi database.
• You can use same SQL SELECT command into PHP
function mysqli_query().
• This function is used to execute SQL command and later
another PHP function mysqli_fetch_assoc() can be used
to fetch all the selected data.
• This function returns row as an associative array, a
numeric array, or both.
• This function returns FALSE if there are no more rows.

6. MySQLi Query Data
• Example:
<?php
// Connection to Database
// Select Database
$sql = 'SELECT fname FROM table1';
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0)
{
while($row = mysqli_fetch_assoc($result))
{
echo "Name: " . $row["name"]. "<br>";
}
}
else
{
echo "0 result";
}
mysqli_close($conn);
?>

7. MySQLi Query Data
• We have seen SQL SELECT command to fetch data from
MySQLi table.
• We can use a conditional clause called WHERE clause to
filter out results.
• Using WHERE clause, we can specify a selection criteria
to select required records from a table.
• The WHERE clause works like an if condition in any
programming language. This clause is used to compare
given value with the field value available in MySQLi table.
• If given value from outside is equal to the available field
value in MySQLi table, then it returns that row.
• You can use same SQL SELECT command with WHERE
CLAUSE into PHP function mysqli_query().

8. MySQLi Query Data
• Example:
<?php
// Connection to Database
// Select Database
$sql = 'SELECT fname FROM table1 WHERE fname=“ahmad”';
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0)
{
while($row = mysqli_fetch_assoc($result))
{
echo "Name: " . $row["name"]. "<br>";
}
}
else
{
echo "0 result";
}
mysqli_close($conn);
?>

9. MySQLi UPDATE Data
• There may be a requirement where existing data in a
MySQLi table needs to be modified.
• You can do so by using SQL UPDATE command.
• This will modify any field value of any MySQLi table.
• You can update one or more field altogether.
• You can specify any condition using WHERE clause.
• You can update values in a single table at a time.
• You can use SQL UPDATE command with or without
WHERE CLAUSE into PHP function mysqli_query().

10. MySQLi UPDATE Data
• Example:
<?php
// Connection to Database
// Select Database
$sql = ' UPDATE table1 SET fname="althamas" WHERE name="ram"';
if (mysqli_query($conn, $sql))
{
echo "Record updated successfully";
}
else
{
echo "Error updating record: " . mysqli_error($conn);
}
mysqli_close($conn);
?>

11. MySQLi DELETE Data
• If you want to delete a record from any MySQLi table,
then you can use SQL command DELETE FROM.
• If WHERE clause is not specified, then all the records will
be deleted from the given MySQLi table.
• You can specify any condition using WHERE clause.
• You can delete records in a single table at a time.
• You can use SQL DELETE command with or without
WHERE CLAUSE into PHP function mysqli_query().