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PHP uses pdo to connect to the access database and display data operations in a loop
PHP uses pdo to connect to the access database and display data operations in a loop
Jun 05, 2018 pm 04:38 PM
This article mainly introduces the operation of PHP using pdo to connect to the access database and display the data in a loop. It analyzes in detail the operation skills and related operations of PHP using pdo to connect to the access database, query, execute sql statements, preprocessing, etc. in the form of examples. Notes, friends in need can refer to
This article describes the example of PHP using pdo to connect to the access database and display the data in a loop. Share it with everyone for your reference, the details are as follows:
PDO connection and query:
try {
$conn = new PDO("odbc:driver={microsoft access driver (*.mdb)};
dbq=".realpath("MyDatabase.mdb"))
or die("鏈接錯誤！");
//echo "鏈接成功！";
}
catch(PDOException $e){
echo $e->getMessage();
}
$sql = "select * from users";1. foreach()Method
foreach ($conn->query($sql) as $row) {
$row["UserID"];
$row["UserName"];
$row["UserPassword"];
}2. while()Method
$rs = $conn->query($sql);
$rs->setFetchMode(PDO::FETCH_NUM);
while($row=$rs->fetch()){
$row[0];
$row[1];
$row[2];
}php uses the PDO abstraction layer to obtain query results. There are three main ways:
(1) PDO::query()Query.
Look at the following php code:
<?php
//PDO::query()查詢
$res = $db->query('select * from user');
$res->setFetchMode(PDO::FETCH_NUM); //數(shù)字索引方式
while ($row = $res->fetch()){
print_r($row);
}
?>(2)PDO->exec()Processing sql
<?php
//PDO->exec()處理sql
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$res = $db->exec("insert into user(id,name) values('','php點點通')");
echo $res;
?>（3）PDO::prepare()Preprocessing execution query
<?php
//PDO::prepare()預(yù)處理執(zhí)行查詢
$res = $db->prepare("select * from user");
$res->execute();
while ($row = $res->fetchAll()) {
print_r($row);
}
?>setAttribute() The method is to set attributes. Common parameters are as follows:
PDO::CASE_LOWER -- Force column names to be lowercase
PDO::CASE_NATURAL -- Column names are in original form
PDO::CASE_UPPER -- Force column names to be uppercase
setFetchModeMethod to set the type of return value for obtaining the result set. Common parameters are as follows:
PDO::FETCH_ASSOC -- Associative array form
PDO::FETCH_NUM -- Numeric index array form
PDO::FETCH_BOTH -- Both array forms are available, this is the default
PDO::FETCH_OBJ -- Follow The form of the object is similar to the previous mysql_fetch_object()
The above is summarized as follows:
The query operation is mainly PDO::query(), PDO: :exec(), PDO::prepare().
PDO->query() — Process a SQL statement and return a "PDOStatement"
PDO->exec() — Process a SQL statement, and returns the number of affected entriesPDO::prepare()Mainly a preprocessing operation, you need to execute the SQL statement in the preprocessing through $rs->execute()
Finally, two commonly used functions are introduced:
(1)fetchColumn()Get the result of a field in the specified record, the default is the first one Field!
<?php $res = $db->query('select * from user'); //獲取指定記錄里第二個字段結(jié)果 $col = $res->fetchColumn(1); echo $col; ?>
(2)fetchAll(), get data from a result set, and then store it in an associative array
<?php $res = $db->query('select * from user'); $res_arr =$res->fetchAll(); print_r($res_arr); ?>
Related recommendations:
PHP ADODB generates HTML table function rs2html function [with error handling function usage]
Example of PHP using regular expressions to filter illegal strings
# #
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