mysql多字搜索

Question

我有一个mysql表和一个搜索表单 我根据给定的条件过滤表格 但我的问题是我想从字符串字段中搜索多个单词 你能帮我解决一下这个问题： 我的意思是我想允许它在字符串中写入多个单词并希望它们被＆＃34; AND＆＃34;

搜索

if ($_REQUEST["string"]<>'') {
    $search_string = " AND (customername LIKE '%".mysql_real_escape_string($_REQUEST["string"])."%' OR definition LIKE '%".mysql_real_escape_string($_REQUEST["string"])."%')"; 
}
if ($_REQUEST["customername"]<>'') {
    $search_customername = " AND customername='".mysql_real_escape_string($_REQUEST["customername"])."'";   
}

if ($_REQUEST["date"]<>'' and ($_REQUEST["string"]<>'' or $_REQUEST["customername"]<>'') ) {
    $sql = "SELECT * from ".$SETTINGS["data_table"]." WHERE date = '".mysql_real_escape_string($_REQUEST["date"])."' ".$search_string.$search_customername;
} else
if ($_REQUEST["date"]<>'' and ($_REQUEST["string"]<>'' or $_REQUEST["customername"]<>'' ) ) {
    $sql = "SELECT * from ".$SETTINGS["data_table"]." WHERE date = '".mysql_real_escape_string($_REQUEST["date"])."' ".$search_string.$search_customername;
} else

if ($_REQUEST["date"]<>'' and $_REQUEST["string"]=='' and $_REQUEST["customername"]=='') {
    $sql = "SELECT * from ".$SETTINGS["data_table"]." WHERE date = '".mysql_real_escape_string($_REQUEST["date"])."' ";
} else {
    $sql = "SELECT * FROM ".$SETTINGS["data_table"]." WHERE id>0".$search_string.$search_customername;
}