Storing database structure_问答_开发者_运维开发者技术经验分享

Is there some tool that can store for me the database structure, say in some xml file or something like that.

And later from the code it can generate for me t开发者_JAVA百科he sql query for this database creation ?

Currently I am working with MySQL , but it probably does not matter .

Just I not want to maintain my self all those things.

In my experience I have used MySQL Workbench to take care of issues like this. If you download Workbench (assuming you don't have it already) from http://wb.mysql.com/ you will have the option to "Create an EER diagram from an existing database." This will create an EER diagram which is a good visual presentation of the database with which you are working. The .mwb file that you can then save can be loaded and then "forward engineered" into local/external database.

Mysqldump is another alternative to use at the command line. It will, by default, dump out the entire schema structure and contained data. However, if you are just looking for database structure including views and routines and you do not care about the data itself then you need to throw some extra parameters into the command.

In my experience Mysqldump is quick and easy whereas EER diagrams are easier to share with others and then forward engineer back onto other DBs from the Workbench application.

EDIT

You should note that just because you export the database create table queries to a .sql file or .mwb file that you can't just copy and paste the text into another platform (Microsoft SQL, Oracle, etc) and expect it to work. Syntax across different versions of SQL is (obviously) different.

THE FOLLOWING ANSWER USES PHP, I am keeping it here for future users.

I wrote code specifically to do that (in PHP):

$db = mysql_connect($dbhost, $dbuser, $dbpass) or die("MySQL Error: " . mysql_error());
mysql_select_db($dbname) or die("MySQL Error: " . mysql_error());

$allTables = Array
    (
      //put all table names in this array
    );
foreach($allTables as $tbl){
    define($tbl, $tbl);
}
$clm = '$columns';
$inds = '$indexes';
$query = "SHOW TABLES IN {$dbname}";
$tables = array();
$result = mysql_query($query) or die("ERROR ONE:".mysql_error());
while($row = mysql_fetch_array($result)){
    $tables[] = $row["Tables_in_{$dbname}"];
}

//TO GET ARRAY FOR TABLE DISPLAY:
$cols = array();
foreach($tables as $tbl){
//    echo "<br/>".
    $query = "SHOW COLUMNS FROM $tbl";
    $cols[$tbl] = array();
    $result = mysql_query($query) or die("ERROR ONE:".mysql_error());
    while($row = mysql_fetch_array($result)){
        $cols[$tbl][] = array('Field'=>$row['Field'],
                              'Type'=>$row['Type'],
                              'Null'=>$row['Null'],
                              'Default'=>$row['Default'],
                              'Extra'=>$row['Extra'],
                        );
    }
}
$index = array();
$query = "SELECT * FROM information_schema.statistics
WHERE TABLE_SCHEMA = '{$dbname}';
"; 
$result = mysql_query($query) or die("ERROR ONE:".mysql_error());
while($row = mysql_fetch_array($result)){

    $index[$row['TABLE_NAME']][] = array('INDEX_NAME'=>$row['INDEX_NAME'],
                          'COLUMN_NAME'=>$row['COLUMN_NAME'],
                          'INDEX_TYPE'=>$row['INDEX_TYPE'],
                          'INDEX_NAME'=>$row['INDEX_NAME'],
                          'SEQ_IN_INDEX'=>$row['SEQ_IN_INDEX'],
                    );
}
//echo "<pre>";print_r($index);
//exit;
//TO GET THE ARRAY VARIABLE
echo "<pre>
&lt;?php
$clm = Array (";
foreach ($cols as $key=>$tbl){
echo "
    $key => Array (";
    foreach($tbl as $col){
        echo "
        Array ( ";
        foreach($col as $k=>$val){
            echo "
            '$k' => \"$val\",";
        }
        echo "
        ),";
    }
    echo "
    ),";
}
echo "
);";
echo "</pre>";
echo "<pre>
$inds = Array (";
foreach ($index as $key=>$tbl){
echo "
    $key => Array (";
    foreach($tbl as $col){
        echo "
        Array ( ";
        foreach($col as $k=>$val){
            echo "
            '$k' => \"$val\",";
        }
        echo "
        ),";
    }
    echo "
    ),";
}
echo "
);
?>";
echo "</pre>";

Paste the result to this in a php file (called currentDB.php).

Then in another file is where the creation happens with the file you created:

define('BY_COL', 'column');
define('BY_IND', 'index');
$allTables = Array
    (
      //put all table names in this array
    );
foreach($allTables as $tbl){
    define($tbl, $tbl);
}

include_once 'currentDB.php';
$query = "SHOW TABLES IN $dbname";
$tables = array();
$result = mysql_query($query) or die("ERROR ONE:".mysql_error());
while($row = mysql_fetch_array($result)){
    $tables[] = $row["Tables_in_$dbname"];
}

$checkTables = checkTables($tables);
echo "THE FOLLOWING TABLES <b>ARE</b> IN THE DB: <br />
    <pre>";print_r(array_diff($allTables,$checkTables));echo "</pre><br />";
if($checkTables){
    echo "THE FOLLOWING TABLES <b>ARE NOT</b> IN THE DB: <br />".
//    "<pre>";print_r($checkTables);echo "</pre><br />";
    "";
    createTables($checkTables);
    $query = "SHOW TABLES IN $dbname";
    $tables = array();
    $result = mysql_query($query) or die("ERROR ONE:".mysql_error());
    while($row = mysql_fetch_array($result)){
    $tables[] = $row["Tables_in_$dbname"];
}

}

//TO GET ARRAY FOR TABLE DISPLAY:
$cols = array();
foreach($tables as $tbl){
//    echo "<br/>".
    $query = "SHOW COLUMNS FROM $tbl";
    $cols[$tbl] = array();
    $result = mysql_query($query) or die("ERROR ONE:".mysql_error());
    while($row = mysql_fetch_array($result)){
        $cols[$tbl][] = array('Field'=>$row['Field'],
                              'Type'=>$row['Type'],
                              'Null'=>$row['Null'],
                              'Default'=>$row['Default'],
                              'Extra'=>$row['Extra'],
                        );
    }
}
$checkTables = checkCols($cols);

if($checkTables){
    echo "THE FOLLOWING COLS <b>ARE DIFFERENT</b> IN THE DB: <br />".
//    "<pre>";print_r($checkTables);echo "</pre><br />".
    "";
    alterTable($checkTables);
}
$index = array();
$query = "SELECT * FROM information_schema.statistics
WHERE TABLE_SCHEMA = '$dbname';
";
$result = mysql_query($query) or die("ERROR ONE:".mysql_error());
while($row = mysql_fetch_array($result)){
    $index[$row['TABLE_NAME']][] = array('INDEX_NAME'=>$row['INDEX_NAME'],
                          'COLUMN_NAME'=>$row['COLUMN_NAME'],
                          'INDEX_TYPE'=>$row['INDEX_TYPE'],
                          'INDEX_NAME'=>$row['INDEX_NAME'],
                          'SEQ_IN_INDEX'=>$row['SEQ_IN_INDEX'],
                    );
}
$checkTables = checkIndexes($index);

if($checkTables){
    echo "THE FOLLOWING INDEXES <b>ARE DIFFERENT</b> IN THE DB: <br />".
//    "<pre>";print_r($checkTables);echo "</pre><br />".
      "";
    alterTable($checkTables,BY_IND);
}
//echo "<pre>";print_r($indexes);echo "</pre><br />";

function  checkTables($array){
    $tbls = $GLOBALS['allTables'];
    $diff = array_diff($tbls,$array);
    if($diff){
        return $diff;
    }
    return array();
}

function  checkCols($array){
    $cols = $GLOBALS['columns'];
    $diff = array_diff_no_cast($cols,$array);
    if($diff){
//        echo "HI<br />";
        return $diff;
    }
    return array();
}

function checkIndexes($array){
    $ind = $GLOBALS['indexes'];
    $diff = array_diff_no_cast($ind,$array);
    if($diff){
//        echo "HI<br />";
        return $diff;
    }
    return array();
}

function createTables($tables){
    $cols = $GLOBALS['columns'];
    $ind = $GLOBALS['indexes'];

    foreach($tables as $t){
        $thisCols = (isset($cols[$t])?$cols[$t]:array());

        $thisInd = (isset($ind[$t])?fromIndex($ind[$t]):array());

        $create = "CREATE TABLE `$t` (\n";
        foreach($thisCols as $k=>$c){
//            echo "<pre>$k\n{$c['Default']}</pre>";
            if($c['Default']=='CURRENT_TIMESTAMP'){
//                echo "IN HERE";
                $c['Extra'] = " ON UPDATE CURRENT_TIMESTAMP";
            }
            $create .= "`{$c['Field']}` {$c['Type']} ".
                    (($c['Null']=='NO')?'NOT NULL':'')." ".
                    ((strlen($c['Default'])>0)?"DEFAULT ".
                    (is_quoted($c['Default'])?"'{$c['Default']}'":"{$c['Default']}"):'').
                    "{$c['Extra']}";
            if(count($thisCols)!==($k+1)){
                $create .= ",\n";
            }
            else
                $create .= "\n";
        }
        $i = 0;
        foreach($thisInd as $k=>$c){
            if($i == 0){
                $create .= ",\n";
            }
            if($c['INDEX_NAME']=='PRIMARY'){
                $create .= "PRIMARY ";
            }
            else{
                $iName = explode("_",$c['INDEX_NAME']);
                if(array_search("UNIQUE",$iName)){
                    $create .= "UNIQUE ";
                }
            }
            $create .= "KEY ".
                (($c['INDEX_NAME']=='PRIMARY')?'':"`{$c['INDEX_NAME']}`")." ({$c['COLUMN_NAME']})";
            if(count($thisInd)!==($i+1)){
                $create .= ",\n";
            }
            else
                $create .= "\n";
//            echo "<pre>";print_r($c);echo "</pre>";
            $i++;
        }
        $create .= ");";
//        echo "<pre>$create</pre>";
        mysql_query($create) or die("ERROR CREATE:".mysql_error());
        echo "CREATED $t<br />";
    }
//    die;
}


function fromIndex($ind){
    $return = array();
    foreach($ind as $i){
        $return[$i['INDEX_NAME']]['INDEX_NAME'] = $i['INDEX_NAME'];
//        echo $i['COLUMN_NAME']." -- <br/>".
        $return[$i['INDEX_NAME']]['COLUMN_NAME'] = (isset($return[$i['INDEX_NAME']]['COLUMN_NAME'])?"{$return[$i['INDEX_NAME']]['COLUMN_NAME']}, `{$i['COLUMN_NAME']}`":"`{$i['COLUMN_NAME']}`");
    }
//    echo "<pre>";print_r($return);echo "</pre>";
//    die;
    return $return;
}
function alterTable($table, $type = BY_COL){
//    echo "<u>";

    switch ($type){
        case BY_COL:
//            echo BY_COL;
            $tbls = $GLOBALS['cols'];
            $realTbls = $GLOBALS['columns'];
//            echo "<pre>";print_r($table);echo"</pre>";
//            die;
            foreach($table as $k=>$t){
//                echo
//                $query = "SHOW COLUMNS FROM $k";
//                echo "<br />";
                foreach($t as $ky=>$col){
//                    echo
                    if($ky == 0){
                        $after = 'FIRST';
                    }
                    else {
                        $after = "AFTER `{$realTbls[$k][$ky-1]['Field']}`";
                    }
                    $primary = false;
                    if($col['Default']=='CURRENT_TIMETAMP'){
                        $col['Extra'] .= " ON UPDATE CURRENT_TIMESTAMP";
                    }
                    if($col['Extra'] == 'auto_increment'){
                        $query2 = "ALTER TABLE  `$k` ADD PRIMARY KEY (  `{$col['Field']}` )";
                        $query3 = "ALTER TABLE `$k` CHANGE COLUMN `{$col['Field']}`
                             `{$col['Field']}` {$col['Type']} ".($col['Null']=='YES'?'NULL':'NOT NULL').
                            ((!empty($col['Default']))? ' DEFAULT '.(is_quoted($col['Default'])?"'{$col['Default']}'":$col['Default']):'').
                            " {$col['Extra']}".
                            " $after;";
                        $primary = true;
                        $col['Extra'] = "";
                    }
//                    echo
                    $query = "ALTER TABLE `$k` ".(field_in_array($tbls[$k],$col['Field'])?"CHANGE COLUMN `{$col['Field']}`":"ADD COLUMN").
                            " `{$col['Field']}` {$col['Type']} ".($col['Null']=='YES'?'NULL':'NOT NULL').
                            ((!empty($col['Default']))? ' DEFAULT '.(is_quoted($col['Default'])?"'{$col['Default']}'":$col['Default']):'').
                            " {$col['Extra']}".
                            " $after;";
//                    echo "<br/>";
                    mysql_query($query) or die("ERROR CREATE: $query".mysql_error());
                    if($primary){
                        mysql_query($query2) or die("ERROR CREATE: $query2".mysql_error());
                        mysql_query($query3) or die("ERROR CREATE: $query3".mysql_error());
                    }
                    echo "ADDED $k: {$col['Field']}";
                    echo "<br />";
                }
//                if($k == 'sessions'){
//                    echo "<pre>$ky:\n";print_r($tbls[$k]);die;
//                }
            }
            break;
        case BY_IND:
//            echo BY_IND;
            $tbls = $GLOBALS['index'];
            foreach($table as $k=>$t){
                $addTbls= fromIndex($table[$k]);
                $thisInd = (isset($tbls[$k])?fromIndex($tbls[$k]):array());
//                echo "<pre>$k:\n";print_r($addTbls);
                foreach($addTbls as $added){
                    $beg = "INDEX";
                    if($added['INDEX_NAME']=='PRIMARY'){
                        $beg = "PRIMARY KEY";
                        $added['INDEX_NAME'] = '';
                    }
                    else{
                        $iName = explode("_",$added['INDEX_NAME']);
                        if(array_search("UNIQUE",$iName)){
                            $beg = "UNIQUE ".$beg;
                        }
                    }
//                    echo
                    $query = "ALTER TABLE `$k` ".(field_in_array($thisInd,$added['INDEX_NAME'],'INDEX_NAME')?"DROP INDEX `{$added['INDEX_NAME']}`, ":'')."ADD $beg `{$added['INDEX_NAME']}` ({$added['COLUMN_NAME']})";
                    mysql_query($query) or die("ERROR CREATE:".mysql_error());
                    echo "ADDED $k: {$added['INDEX_NAME']}";
                    echo "<br />";
                }
            }
//            die;
            break;
    }
//    echo "</u><br />";

}

function is_quoted($str){
    if(is_numeric($str))
        return false;
    if($str == 'CURRENT_TIMESTAMP')
        return false;
    return true;
}

function field_in_array($arr, $field, $type = 'Field'){
    foreach($arr as $val){
//        echo "HERE: $field, $type";
//        print_r($val);echo "<br/>";
        if($val[$type]==$field){
//            echo "HI";
            return true;
        }
    }
    return false;
}

   ##################################
   #    FUNCTION - multidim diff    #
   ##################################

function array_diff_no_cast(&$ar1, &$ar2) {
   $diff = Array();
   foreach ($ar1 as $key => $val1) {
       foreach($val1 as $k=>$val2){
          if (!isset($ar2[$key]) || array_search($val2, $ar2[$key]) === false) {
             $diff[$key][$k] = $val2;
          }
       }
   }
   return $diff;
}

You can export your database with Mysqldump. The web page has all the details on how to use it.

If you want the SQL to create the table, you can use:

SHOW CREATE TABLE tblname

If you have data, foreign keys, stored procedures and views in your database then the MySQL Workbench can forward reverse all that for you.

For MySQL and others, you might want to try the DESCRIBE TABLE.

You might want to look into the mysqldump utility. It will create a copy of your database in SQL format. (Note to avoid a problem I ran into: Be sure to run it with --routines if you want to also capture your stored functions and procedures!)

A typical command would look something like this:

mysqldump --routines -Q --opt -p -u username databasename >savefile.sql

Also, for large databases, these files can get quite large. You might also want to consider gzipping them or otherwise compressing them on the fly, using something like:

mysqldump --routines -Q --opt -p -u username databasename | gzip >savefile.sql.gz

use phpMyAdmin u can export your structure to XML,SQL,CSV and many other by using export option

Storing database structure

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