Examples of common database operations in Drupal7

1. Insert a single record

db_insert("table")->fields(array('field1' => 'value1', 'field2' => 'value2', 'fieldn' => $valuen))->execute();

2. Insert multiple records

$values[] = array('field1' => 'val1', 'field2' => 'val2', 'fieldn' => $valn);
$values[] = array('field1' => 'value1', 'field2' => 'value2', 'fieldn' => $valuen);
$query = db_insert( ' table')->fields(array('field1', 'field2', 'fieldn'));
foreach ($values as $record) {
   $query->values($record);
}
$query->execute();

3. Update a record

db_update('imports')
   ->condition('name', 'Chico')
   ->fields(array('address' => 'Go West St.'))
   ->execute();
// Is equal to: 
UPDATE {imports} SET address = 'Go West St.' WHERE name = 'Chico';

Delete a record

db_delete('imports')
   ->condition('name' => 'Zeppo')
   ->execute();

5. Merge records

db_merge('people')
  ->key(array('job' => 'Speaker'))
  ->insertFields(array('age' => 31,'name' => 'Meredith'))
  ->updateFields(array('name' => 'Tiffany'))
  ->execute();
// If there is job for Speaker the 1 If a record is entered, it is updated name for Tiffany If it does not exist, insert it 1 article age for 31 . name for Meredith . job for Speaker The record. 

6. Automatically increment the value of a field in the database by 1 or by itself.

db_update('example_table')
  ->expression('count', 'count + 1')
  ->condition('field1', $some_value)
  ->expression('field2', 'field2 + :inc', array(':inc' => 2))
  ->execute();

Select * from database where name = 1; select * from database where name = 1;

$query = db_select('node', 'n');
$query->addField('n', 'name', 'label');
$query->addField('n', 'name', 'value');