我创建了一个与 codeigniter 函数基本相同的辅助batch_update()
函数。
但具有更新索引本身的能力。新值由 定义index_update_key
。
function update_batch($db, $table = '', $set = NULL, $index = NULL, $index_update_key = '') {
if ($table === '' || is_null($set) || is_null($index) || !is_array($set)) {
return FALSE;
}
$sql = 'UPDATE ' . $db->protect_identifiers($table) . ' SET ';
$ids = $when = array();
$cases = '';
//generate the WHEN statements from the set array
foreach ($set as $key => $val) {
$ids[] = $val[$index];
foreach (array_keys($val) as $field) {
if ($field != $index && $field != $index_update_key) {
$when[$field][] = 'WHEN ' . $db->protect_identifiers($index)
. ' = ' . $db->escape($val[$index]) . ' THEN ' . $db->escape($val[$field]);
} elseif ($field == $index) {
//if index should also be updated use the new value specified by index_update_key
$when[$field][] = 'WHEN ' . $db->protect_identifiers($index)
. ' = ' . $db->escape($val[$index]) . ' THEN ' . $db->escape($val[$index_update_key]);
}
}
}
//generate the case statements with the keys and values from the when array
foreach ($when as $k => $v) {
$cases .= "\n" . $db->protect_identifiers($k) . ' = CASE ' . "\n";
foreach ($v as $row) {
$cases .= $row . "\n";
}
$cases .= 'ELSE ' . $k . ' END, ';
}
$sql .= substr($cases, 0, -2) . "\n"; //remove the comma of the last case
$sql .= ' WHERE ' . $index . ' IN (' . implode(',', $ids) . ')';
return $db->query($sql);
}
现在我可以执行以下操作
$set = array(
array(
'token' => '657871316787544',
'device' => 'none',
'new_token_value' => ''
),
array(
'token' => '757984513154644',
'device' => 'none',
'new_token_value' => ''
)
);
update_batch($this->db, 'table_name', $set, 'token', 'new_token_value');
并且sql输出是
UPDATE `b2c` SET
`token` = CASE
WHEN `token` = '657871316787544' THEN ''
WHEN `token` = '757984513154644' THEN ''
ELSE token END,
`device` = CASE
WHEN `token` = '657871316787544' THEN 'none'
WHEN `token` = '757984513154644' THEN 'none'
ELSE device END
WHERE token IN (657871316787544,757984513154644)