在我的代码中,我正在检查数据库中是否存在值。如果确实存在,则应返回错误。但是,如果不存在,则应在数据库中创建该值。这是我的代码:
/**
* Check if the string has been used before
*
* @return bool
*/
private function _checkStringBeenUsed ()
{
echo "Running check!\n";
if ($this->_sString === null) {
parent::showErrorMessage('Invalid shared String', 1005);
}
$this->_validateString();
$sSql = "SELECT * FROM operator_string WHERE
operatorId = '{$this->_sOperator}' AND
sharedString = '{$this->_sString}' AND
time >= DATE_SUB(
NOW(),
INTERVAL 1 DAY
)";
$rQur = $this->_oDb->query($sSql);
echo $sSql;
echo "\n\n";
echo "Rows: " . $rQur->num_rows;
echo "\n\n";
if ($rQur->num_rows > 0) {
parent::showErrorMessage('Shared string already used', 1005);
} else {
$sSql = "INSERT INTO operator_string
(operatorId, sharedString, time, hash)
VALUES
('{$this->_sOperator}',
'{$this->_sString}',
NOW(),
'{$this->_sHash}'
)";
$this->_oDb->query($sSql);
}
}
/**
* Validates the string and the hash
*
* @return void
*/
private function _validateString ()
{
$sHashString = $this->_sOperator . $this->_sSharedSecret . $this->_sString;
$sHash = hash('sha256', $sHashString);
if ($sHash != $this->_sHash) {
parent::showErrorMessage('Invalid authentication hash send', 1006);
}
}
这是我从 iPhone 运行命令时的输出:
2013-03-27 21:43:08.560 MyApp[45315:c07] Result: Running check!
SELECT * FROM operator_string WHERE
operatorId = 'a8198231u82' AND
sharedString = 'cqCEYGIbNvF7HU1' AND
time >= DATE_SUB(
NOW(),
INTERVAL 1 DAY
)
Rows: 1
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE error>
<error>
<errorCode>1005</errorCode>
<errorMessage>Shared string already used</errorMessage>
</error>
如果在运行调用之前表中没有数据,它怎么可能是 1 行?该方法只运行一次,插入完成后执行选择。
编辑 1
如果我注释掉插入 SQL 行,它不会向数据库添加任何内容。