虽然这个问题已经很老了，但如果你使用的是mysql workbench 6.3，你可以这样做。(很可能它也适用于其他版本)

右键点击你的模式和“搜索表数据”，输入你的值，然后点击“开始搜索”。这是它。

这是我知道的最简单的方法。 在PHPMyAdmin中选择你的DB，然后转到“搜索”选项卡，写下你想要找到的内容以及你要搜索的位置。如果要从所有表中搜索单词，则选择所有表。然后“开始”，看看结果。

PHP函数:

function searchAllDB($search){
    global $mysqli;
    
    $out = Array();
    
    $sql = "show tables";
    $rs = $mysqli->query($sql);
    if($rs->num_rows > 0){
        while($r = $rs->fetch_array()){
            $table = $r[0];
            $sql_search = "select * from `".$table."` where ";
            $sql_search_fields = Array();
            $sql2 = "SHOW COLUMNS FROM `".$table."`";
            $rs2 = $mysqli->query($sql2);
            if($rs2->num_rows > 0){
                while($r2 = $rs2->fetch_array()){
                    $column = $r2[0];
                    $sql_search_fields[] = "`".$column."` like('%".$mysqli->real_escape_string($search)."%')";
                }
                $rs2->close();
            }
            $sql_search .= implode(" OR ", $sql_search_fields);
            $rs3 = $mysqli->query($sql_search);
            $out[$table] = $rs3->num_rows."\n";
            if($rs3->num_rows > 0){
                $rs3->close();
            }
        }
        $rs->close();
    }
    
    return $out;
}

print_r(searchAllDB("search string"));

使用MySQL Workbench可以很容易地选择几个表，并在所有这些数据库表中搜索文本;-)

这个解决方案 a)只有MySQL，不需要其他语言，并且 b)返回SQL结果，准备处理!

#Search multiple database tables and/or columns
#Version 0.1 - JK 2014-01
#USAGE: 1. set the search term @search, 2. set the scope by adapting the WHERE clause of the `information_schema`.`columns` query
#NOTE: This is a usage example and might be advanced by setting the scope through a variable, putting it all in a function, and so on...

#define the search term here (using rules for the LIKE command, e.g % as a wildcard)
SET @search = '%needle%';

#settings
SET SESSION group_concat_max_len := @@max_allowed_packet;

#ini variable
SET @sql = NULL;

#query for prepared statement
SELECT
    GROUP_CONCAT("SELECT '",`TABLE_NAME`,"' AS `table`, '",`COLUMN_NAME`,"' AS `column`, `",`COLUMN_NAME`,"` AS `value` FROM `",TABLE_NAME,"` WHERE `",COLUMN_NAME,"` LIKE '",@search,"'" SEPARATOR "\nUNION\n") AS col
INTO @sql
FROM `information_schema`.`columns`
WHERE TABLE_NAME IN
(
    SELECT TABLE_NAME FROM `information_schema`.`columns`
    WHERE
        TABLE_SCHEMA IN ("my_database")
        && TABLE_NAME IN ("my_table1", "my_table2") || TABLE_NAME LIKE "my_prefix_%"
);

#prepare and execute the statement
PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

我要用这个。你只需要改变变量

$query ="SELECT `column_name` FROM `information_schema`.`columns` WHERE `table_schema`='" . $_SESSION['db'] . "' AND `table_name`='" . $table . "' ";
$stmt = $dbh->prepare($query);
$stmt->execute(); 
$columns = $stmt->fetchAll(PDO::FETCH_ASSOC);       

$query="SELECT name FROM `" . $database . "`.`" . $table . "` WHERE ( ";
foreach ( $columns as $column ) {
    $query .=" CONVERT( `" . $column['column_name'] . "` USING utf8 ) LIKE '%" . $search . "%' OR ";
}
$query = substr($query, 0, -3);
$query .= ")";

echo $query . "<br>";
$stmt=$dbh->prepare($query);
$stmt->execute();
$results = $stmt->fetchAll(PDO::FETCH_ASSOC);
echo "<pre>";
print_r ($results );
echo "</pre>";