所以我有这个代码从一个表中选择数据，将其提取到一个数组中并将其插入另一个表中。一切正常，直到我尝试在步骤5中执行CREATE语句，这给了我这个错误：
Incorrect database name 'EN'
我就像“什么？我的代码中没有提到'EN'。” 你知道，我有点绝望，因为问我不想伤害我想我也可以把问题抛到这里。也许我很幸运，有人发现了一些东西，我不知道 无论如何，谢谢！
我认为不需要整个代码，但我不想冒任何风险，所以这就是：
<?php
// ---------------------------------------------STEP 1: CONNECT TO DB---------------------------------------------
$host = "localhost";
$user = "****";
$pass = "****";
$db = "customerfinder";
$con = new mysqli($host, $user, $pass, $db);
if($con->connect_error)
{
die("Connection failed (" . $con->connect_error . ")");
}
// ---------------------------------------------STEP 2: STORE COUNTRY CODES & NAMES---------------------------------------------
// Note: In the database exist rows like "Last Updated: 10/17/2014". The WHERE clause exists because of that.
$query = "SELECT DISTINCT Country_Code, Country_Name FROM TData WHERE Country_Code<>'' AND Country_Name<>''";
$result = $con->query($query);
// $countries will be used as an associative array with all country codes
$countries = array();
if($result->num_rows > 0)
{
// Every row is fetched into an associative array
while($row = $result->fetch_assoc())
{
$country_code = $row["Country_Code"];
$country_name = $row["Country_Name"];
// The first part of the array $countries is made.
// At the moment, $countries looks like this: array("COUNTRY_CODE" => array("Name" => "COUNTRY_NAME"))
$countries[$country_code] = array(
"Name" => $country_name
);
}
}
// ---------------------------------------------STEP 3: STORE REMAINING VALUES---------------------------------------------
$query = "SELECT DISTINCT Country_Code, Series_Code, 2012_YR2012 FROM TData WHERE Country_Code<>'' AND Series_Code<>'' AND 2012_YR2012<>''";
$result = $con->query($query);
// $series_codes will be used as an indexed array which contains all the codes of 2012_YR2012.
// It will be used for creating dynamic INSERT statements.
$series_codes = array();
// $series_codes_first will be used as a string which stores the first series code
$series_codes_first = "";
// $series_codes_insert is a boolean which is set to false once the current code matches $series_codes_first,
// so the codes do not get stored multiple times
$series_codes_insert = true;
if($result->num_rows > 0)
{
while($row = $result->fetch_assoc())
{
$country_code = $row["Country_Code"];
$series_code = $row["Series_Code"];
$series_value = $row["2012_YR2012"];
// If $series_codes_first is equal to $series_code all the codes have been stored
// and $series_codes_insert is set to false
if($series_codes_first == $series_code)
{
$series_codes_insert = false;
}
// If $series_codes_insert is set to true the series codes are added to $series_codes
if($series_codes_insert == true)
{
array_push($series_codes, $series_code);
}
// If $series_codes_first is empty it is the first loop and the first code gets stored to be checked later
if($series_codes_first == "")
{
$series_codes_first = $series_code;
}
// The series values are added to $countries.
// Now $countries looks like this: array("COUNTRY_CODE" => array("Name" => "COUNTRY_NAME", "SERIES_CODE" => "SERIES_VALUE"))
$countries[$country_code][$series_code] = $series_value;
}
}
// ---------------------------------------------STEP 4: CHECK (AND DROP) TCOUNTRIES---------------------------------------------
$drop_query = "DROP TABLE TCountries";
$drop_feedback;
$check_query = "SHOW TABLES LIKE 'TCountries'";
// If $result contains no rows, TCountries does not exist and $drop_query has not to be used
$result = $con->query($check_query);
if($result->num_rows == 0)
{
$drop_feedback = "TCountries did not exist and was therefore not dropped!";
}
else
{
if($con->query($drop_query))
{
$drop_feedback = "TCountries was successfully dropped!";
}
else
{
$drop_feedback = "An error occurred while trying to drop TCountries (" . $con->error . ")";
}
}
// ---------------------------------------------STEP 5: CREATE TCOUNTRIES---------------------------------------------
$create_query = "CREATE TABLE TCountries(Country_Code VARCHAR(3) PRIMARY KEY, Country_Name VARCHAR(20)";
// The series codes are added to $create_query one after another
foreach($series_codes as $value)
{
$create_query .= ", " . $value . " VARCHAR(15)";
}
$create_query .= ")";
$create_feedback;
if($con->query($create_query))
{
$create_feedback = "TCountries was successfully created!";
}
else
{
$create_feedback = "An error occurred while trying to create TCountries (" . $con->error . ")";
}
// ---------------------------------------------STEP 6: INSERT COUNTRIES---------------------------------------------
$insert_feedback = "";
// Every country is inserted separately
foreach($countries as $country_code => $country)
{
$insert_query = "INSERT INTO TCountries VALUES('" . $country_code . "'";
// The series values are added to $insert_query one after another
foreach($country as $value)
{
$insert_query .= ", '" . $value . "'";
}
$insert_query .= ")";
if($con->query($insert_query))
{
$insert_feedback .= "<br>Dataset was successfully inserted!";
}
else
{
$insert_feedback .= "<br>An error occurred while trying to insert the dataset (" . $con->error . ")";
}
}
// ---------------------------------------------CHECK DATA---------------------------------------------
echo "<h2>List</h2>";
foreach($countries as $country_code => $country)
{
echo "<b>" . $country_code . "</b><br>";
foreach($country as $key => $value)
{
echo $key . ": " . $value . "<br>";
}
echo "</p>";
}
echo "<h2>JSON</h2>";
$countries_json = json_encode($countries, JSON_PRETTY_PRINT);
echo $countries_json;
echo "<h2>Array</h2>";
print_r($countries);
echo "<h3>\$series_codes</h3>";
print_r($series_codes);
echo "<h3>Query feedbacks</h3>";
echo $drop_feedback . "<br>";
echo $create_feedback;
echo $insert_feedback;
?>
答案 0 :(得分：0)
点.被视为mysql中数据库/表/列之间的分隔符。即使您连接到数据库SELECT * FROM foo.table而不是bar，也可以使用foo。
您正在从另一个数据库动态创建列，因此如果这些名称包含点，则可以在查询中用反引号（`）将它们括起来表示完整列名称：
$create_query .= ", `" . $value . "` VARCHAR(15)";
^-- here ^-- and here