我如何获得当前的AUTO_INCREMENT值为一个表在MySQL?
当前回答
列出dbname所有tabename和AUTO_INCREMENT
SELECT `AUTO_INCREMENT`,`TABLE_NAME`
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'dbname' ORDER BY AUTO_INCREMENT desc
其他回答
如果列在sql server中是自动递增的,那么要查看当前自动递增的值,如果您想编辑该列的值,请使用以下查询。
-- to get current value
select ident_current('Table_Name')
-- to update current value
dbcc checkident ('[Table_Name]',reseed,"Your Value")
Mysqli可执行示例代码:
<?php
$db = new mysqli("localhost", "user", "password", "YourDatabaseName");
if ($db->connect_errno) die ($db->connect_error);
$table=$db->prepare("SHOW TABLE STATUS FROM YourDatabaseName");
$table->execute();
$sonuc = $table->get_result();
while ($satir=$sonuc->fetch_assoc()){
if ($satir["Name"]== "YourTableName"){
$ai[$satir["Name"]]=$satir["Auto_increment"];
}
}
$LastAutoIncrement=$ai["YourTableName"];
echo $LastAutoIncrement;
?>
查询一个给定模式下的所有表的AUTO_INCREMENT的“使用率”百分比(bigint类型unsigned列除外):
SELECT
c.TABLE_NAME,
c.COLUMN_TYPE,
c.MAX_VALUE,
t.AUTO_INCREMENT,
IF (c.MAX_VALUE > 0, ROUND(100 * t.AUTO_INCREMENT / c.MAX_VALUE, 2), -1) AS "Usage (%)"
FROM
(SELECT
TABLE_SCHEMA,
TABLE_NAME,
COLUMN_TYPE,
CASE
WHEN COLUMN_TYPE LIKE 'tinyint(1)' THEN 127
WHEN COLUMN_TYPE LIKE 'tinyint(1) unsigned' THEN 255
WHEN COLUMN_TYPE LIKE 'smallint(%)' THEN 32767
WHEN COLUMN_TYPE LIKE 'smallint(%) unsigned' THEN 65535
WHEN COLUMN_TYPE LIKE 'mediumint(%)' THEN 8388607
WHEN COLUMN_TYPE LIKE 'mediumint(%) unsigned' THEN 16777215
WHEN COLUMN_TYPE LIKE 'int(%)' THEN 2147483647
WHEN COLUMN_TYPE LIKE 'int(%) unsigned' THEN 4294967295
WHEN COLUMN_TYPE LIKE 'bigint(%)' THEN 9223372036854775807
WHEN COLUMN_TYPE LIKE 'bigint(%) unsigned' THEN 0
ELSE 0
END AS "MAX_VALUE"
FROM
INFORMATION_SCHEMA.COLUMNS
WHERE EXTRA LIKE '%auto_increment%'
) c
JOIN INFORMATION_SCHEMA.TABLES t ON (t.TABLE_SCHEMA = c.TABLE_SCHEMA AND t.TABLE_NAME = c.TABLE_NAME)
WHERE
c.TABLE_SCHEMA = 'YOUR_SCHEMA'
ORDER BY
`Usage (%)` DESC;
我也在寻找相同的方法,最终在Helper类中创建了一个静态方法(在我的情况下,我将其命名为App\Helpers\Database)。
该方法
/**
* Method to get the autoincrement value from a database table
*
* @access public
*
* @param string $database The database name or configuration in the .env file
* @param string $table The table name
*
* @return mixed
*/
public static function getAutoIncrementValue($database, $table)
{
$database ?? env('DB_DATABASE');
return \DB::select("
SELECT AUTO_INCREMENT
FROM information_schema.TABLES
WHERE TABLE_SCHEMA = '" . env('DB_DATABASE') . "'
AND TABLE_NAME = '" . $table . "'"
)[0]->AUTO_INCREMENT;
}
要调用该方法并获得MySql的AUTO_INCREMENT,只需使用以下命令:
$auto_increment = \App\Helpers\Database::getAutoIncrementValue(env('DB_DATABASE'), 'your_table_name');
希望能有所帮助。
如果你只是想知道这个数字,而不是在查询中得到它,那么你可以使用:
SHOW CREATE TABLE tablename;
您应该在底部看到auto_increment