Some common PHP functions and examples

$DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); Copy Code Mysql_data_seek move the internal query pointer to the query line syntax bool Mysql_data_seek (Resource Result_indetifier,int row_number) Example: $DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); $res =mysql_query ("SELECT * from PRODUCT"); $row =mysql_fetch_array ($res); for ($i =0; $i < $num; $i + +) $row =mysql_fetch_array ($res); Mysql_data_seek ($res, 0);//move the pointer back to the first line of the query fruit Copy Code Mysql_fetch_array The result of the query exists in the array (one record per array element) syntax array mysql_fetch_array (Resource Result[,int result_type]) Example: $DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); $res =mysql_query ("SELECT * from PRODUCT"); $row =mysql_fetch_array ($res); Copy Code Mysql_fetch_object gets a row of query results, and is stored as object type, with Mysql_fetch_array () using exactly the same method, except that mysql_fetch_object () can only get query results by field name Echo $ row->fieldname; Correct usage echo $row->0; Error Usage Syntax Object Mysql_fetch_object (resource result) Example: $DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); $res =mysql_query ("SELECT * from PRODUCT"); $row = $mysql _fetch_object ($res); while ($row) { echo $row àp_id; echo $row Àp_name; } Copy Code mysql_insert_id after adding a piece of information using the Insert command, you can take advantage of this function to get an example of the unique ID syntax int mysql_insert_id ([esource Link_identifier]) that just added the record: $DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); $SQLStr "INSERT into produce (p_id,p_name) VALUES (', ' PHP book ')"; $res =mysql_query ($res); $p _id=mysql_insert_id (); Copy Code Mysql_num_rows get query Results There are several lines of syntax int mysql_num_rows (resource result) Example: $DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); $res =mysql_query ("SELECT * from PRODUCT"); $num =mysql_num_rows ($res); Copy Code Mysql_query sends out an example of a SQL syntax query statement syntax resource mysql_query (string Query[,resource link_identifier]): $DB _host = "localhost"; $DB _login = "root"; $DB _password= "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); $res =mysql_query ("SELECT * from PRODUCT"); Copy Code mysql_select_db Select the database name to access syntax bool mysql_select_db (string Database_name[,resource link_identifier]) Example: $DB _host = "localhost"; $DB _login = "root"; $DB _password = "123456"; $DB _name = "Flag"; $conn =mysql_connect ($DB _host, $DB _login, $DB _password); mysql_select_db ($DB _name); Copy Code 1 2 3 Next last page

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