SQL Server: パスワードを保持したまま別のログインを作成する

あるログインを、パスワードはそのままでログイン名だけ変更したいケースがあったのでやり方を調べました。

#### 参考ドキュメント
https://support.microsoft.com/ja-jp/help/918992/how-to-transfer-logins-and-passwords-between-instances-of-sql-server

#### 手順
１．上記ドキュメントで紹介してある以下のクエリを実行してストアドプロシージャを作成

```sql
USE master
GO
IF OBJECT_ID ('sp_hexadecimal') IS NOT NULL
DROP PROCEDURE sp_hexadecimal
GO
CREATE PROCEDURE sp_hexadecimal
@binvalue varbinary(256),
@hexvalue varchar (514) OUTPUT
AS
DECLARE @charvalue varchar (514)
DECLARE @i int
DECLARE @length int
DECLARE @hexstring char(16)
SELECT @charvalue = '0x'
SELECT @i = 1
SELECT @length = DATALENGTH (@binvalue)
SELECT @hexstring = '0123456789ABCDEF'
WHILE (@i <= @length)
BEGIN
DECLARE @tempint int
DECLARE @firstint int
DECLARE @secondint int
SELECT @tempint = CONVERT(int, SUBSTRING(@binvalue,@i,1))
SELECT @firstint = FLOOR(@tempint/16)
SELECT @secondint = @tempint - (@firstint*16)
SELECT @charvalue = @charvalue +
SUBSTRING(@hexstring, @firstint+1, 1) +
SUBSTRING(@hexstring, @secondint+1, 1)
SELECT @i = @i + 1
END

SELECT @hexvalue = @charvalue
GO

IF OBJECT_ID ('sp_help_revlogin') IS NOT NULL
DROP PROCEDURE sp_help_revlogin
GO
CREATE PROCEDURE sp_help_revlogin @login_name sysname = NULL AS
DECLARE @name sysname
DECLARE @type varchar (1)
DECLARE @hasaccess int
DECLARE @denylogin int
DECLARE @is_disabled int
DECLARE @PWD_varbinary varbinary (256)
DECLARE @PWD_string varchar (514)
DECLARE @SID_varbinary varbinary (85)
DECLARE @SID_string varchar (514)
DECLARE @tmpstr varchar (1024)
DECLARE @is_policy_checked varchar (3)
DECLARE @is_expiration_checked varchar (3)

DECLARE @defaultdb sysname

IF (@login_name IS NULL)
DECLARE login_curs CURSOR FOR

SELECT p.sid, p.name, p.type, p.is_disabled, p.default_database_name, l.hasaccess, l.denylogin FROM
sys.server_principals p LEFT JOIN sys.syslogins l
ON ( l.name = p.name ) WHERE p.type IN ( 'S', 'G', 'U' ) AND p.name <> 'sa'
ELSE
DECLARE login_curs CURSOR FOR


SELECT p.sid, p.name, p.type, p.is_disabled, p.default_database_name, l.hasaccess, l.denylogin FROM
sys.server_principals p LEFT JOIN sys.syslogins l
ON ( l.name = p.name ) WHERE p.type IN ( 'S', 'G', 'U' ) AND p.name = @login_name
OPEN login_curs

FETCH NEXT FROM login_curs INTO @SID_varbinary, @name, @type, @is_disabled, @defaultdb, @hasaccess, @denylogin
IF (@@fetch_status = -1)
BEGIN
PRINT 'No login(s) found.'
CLOSE login_curs
DEALLOCATE login_curs
RETURN -1
END
SET @tmpstr = '/* sp_help_revlogin script '
PRINT @tmpstr
SET @tmpstr = '** Generated ' + CONVERT (varchar, GETDATE()) + ' on ' + @@SERVERNAME + ' */'
PRINT @tmpstr
PRINT ''
WHILE (@@fetch_status <> -1)
BEGIN
IF (@@fetch_status <> -2)
BEGIN
PRINT ''
SET @tmpstr = '-- Login: ' + @name
PRINT @tmpstr
IF (@type IN ( 'G', 'U'))
BEGIN -- NT authenticated account/group

SET @tmpstr = 'CREATE LOGIN ' + QUOTENAME( @name ) + ' FROM WINDOWS WITH DEFAULT_DATABASE = [' + @defaultdb + ']'
END
ELSE BEGIN -- SQL Server authentication
-- obtain password and sid
SET @PWD_varbinary = CAST( LOGINPROPERTY( @name, 'PasswordHash' ) AS varbinary (256) )
EXEC sp_hexadecimal @PWD_varbinary, @PWD_string OUT
EXEC sp_hexadecimal @SID_varbinary,@SID_string OUT

-- obtain password policy state
SELECT @is_policy_checked = CASE is_policy_checked WHEN 1 THEN 'ON' WHEN 0 THEN 'OFF' ELSE NULL END FROM sys.sql_logins WHERE name = @name
SELECT @is_expiration_checked = CASE is_expiration_checked WHEN 1 THEN 'ON' WHEN 0 THEN 'OFF' ELSE NULL END FROM sys.sql_logins WHERE name = @name

SET @tmpstr = 'CREATE LOGIN ' + QUOTENAME( @name ) + ' WITH PASSWORD = ' + @PWD_string + ' HASHED, SID = ' + @SID_string + ', DEFAULT_DATABASE = [' + @defaultdb + ']'

IF ( @is_policy_checked IS NOT NULL )
BEGIN
SET @tmpstr = @tmpstr + ', CHECK_POLICY = ' + @is_policy_checked
END
IF ( @is_expiration_checked IS NOT NULL )
BEGIN
SET @tmpstr = @tmpstr + ', CHECK_EXPIRATION = ' + @is_expiration_checked
END
END
IF (@denylogin = 1)
BEGIN -- login is denied access
SET @tmpstr = @tmpstr + '; DENY CONNECT SQL TO ' + QUOTENAME( @name )
END
ELSE IF (@hasaccess = 0)
BEGIN -- login exists but does not have access
SET @tmpstr = @tmpstr + '; REVOKE CONNECT SQL TO ' + QUOTENAME( @name )
END
IF (@is_disabled = 1)
BEGIN -- login is disabled
SET @tmpstr = @tmpstr + '; ALTER LOGIN ' + QUOTENAME( @name ) + ' DISABLE'
END
PRINT @tmpstr
END

FETCH NEXT FROM login_curs INTO @SID_varbinary, @name, @type, @is_disabled, @defaultdb, @hasaccess, @denylogin
END
CLOSE login_curs
DEALLOCATE login_curs
RETURN 0
GO
```
出展：https://support.microsoft.com/ja-jp/help/918992/how-to-transfer-logins-and-passwords-between-instances-of-sql-server

２．作成したストアドを実行

```sql
execute sp_help_revlogin
```

![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/148310/df4e7820-055b-071a-1b52-8d7ed81eb925.png)

↑のようにCREATE LOGIN文が生成される。

CREATE文をコピーし、作成したいログイン名に書き換え＋「SID」だけパラメータからカット
![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/148310/d1ba7c92-4e17-3a7a-1b1a-7461730a4f86.png)
↓
![image.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/148310/2566c6d0-6240-06e7-5e94-cd716e40674b.png)

以上です。
※紐づいている権限は今回の手法だと移行されないので、やりたい場合は別途移行が必要です。