SQL script pour modifier TOUTES les clés étrangères pour ajouter ON DELETE CASCADE

Question

J'ai une base de données SQL 2005 avec environ 250 tables.

Je veux activer temporairement la fonction ON DELETE CASCADE pour toutes les clés étrangères afin de pouvoir effectuer facilement une suppression en masse.

Je veux ensuite désactiver l'option CASCADE DELETE sur toutes les clés étrangères.

La seule façon que je connaisse de faire cela, est d'utiliser Management Studio pour générer une base de données complète, créer script, faire une sorte de recherche et remplacement pour enlever tout sauf les clés étrangères, sauvegarder le script, puis faire encore quelques recherches et remplacements pour ajouter le ON DELETE CASCADE.

Ensuite, je lance le script, je fais ma suppression, puis je lance l'autre script.

Existe-t-il un moyen plus simple de produire ce script ? Cette méthode semble beaucoup trop sujette aux erreurs et je devrai maintenir le script à jour avec toutes les autres modifications que nous apportons à la base de données, ou le re-générer manuellement chaque fois que je pourrais avoir besoin de l'utiliser.

Existe-t-il une option alternative consistant à exécuter un select sur les tables du système pour "générer" le script pour moi ? Serait-il même possible d'exécuter une mise à jour sur une table système qui active et désactive ON DELETE CASCADE ?

Answer 1

Voici un script que j'ai utilisé dans un but similaire. Il ne prend pas en charge les clés étrangères composites (qui utilisent plus d'un champ.) Et il faudrait probablement le modifier avant qu'il ne fonctionne dans votre situation. EDIT : En particulier, il ne gère pas correctement les clés étrangères multi-colonnes.

select
  DropStmt = 'ALTER TABLE [' + ForeignKeys.ForeignTableSchema + 
      '].[' + ForeignKeys.ForeignTableName + 
      '] DROP CONSTRAINT [' + ForeignKeys.ForeignKeyName + ']; '
,  CreateStmt = 'ALTER TABLE [' + ForeignKeys.ForeignTableSchema + 
      '].[' + ForeignKeys.ForeignTableName + 
      '] WITH CHECK ADD CONSTRAINT [' +  ForeignKeys.ForeignKeyName + 
      '] FOREIGN KEY([' + ForeignKeys.ForeignTableColumn + 
      ']) REFERENCES [' + schema_name(sys.objects.schema_id) + '].[' +
  sys.objects.[name] + ']([' +
  sys.columns.[name] + ']) ON DELETE CASCADE; '
 from sys.objects
  inner join sys.columns
    on (sys.columns.[object_id] = sys.objects.[object_id])
  inner join (
    select sys.foreign_keys.[name] as ForeignKeyName
     ,schema_name(sys.objects.schema_id) as ForeignTableSchema
     ,sys.objects.[name] as ForeignTableName
     ,sys.columns.[name]  as ForeignTableColumn
     ,sys.foreign_keys.referenced_object_id as referenced_object_id
     ,sys.foreign_key_columns.referenced_column_id as referenced_column_id
     from sys.foreign_keys
      inner join sys.foreign_key_columns
        on (sys.foreign_key_columns.constraint_object_id
          = sys.foreign_keys.[object_id])
      inner join sys.objects
        on (sys.objects.[object_id]
          = sys.foreign_keys.parent_object_id)
        inner join sys.columns
          on (sys.columns.[object_id]
            = sys.objects.[object_id])
           and (sys.columns.column_id
            = sys.foreign_key_columns.parent_column_id)
    ) ForeignKeys
    on (ForeignKeys.referenced_object_id = sys.objects.[object_id])
     and (ForeignKeys.referenced_column_id = sys.columns.column_id)
 where (sys.objects.[type] = 'U')
  and (sys.objects.[name] not in ('sysdiagrams'))

Answer 2

Réponse d'Andomar La méthode ci-dessus est bonne mais ne fonctionne que pour les contraintes de clé étrangère à une colonne. Je l'ai adapté un peu pour les contraintes multi-colonnes :

create function dbo.fk_columns (@constraint_object_id int)
returns varchar(255)
as begin
declare @r varchar(255)
select @r = coalesce(@r + ',', '') + c.name
from sys.foreign_key_columns fkc
join sys.columns c
  on  fkc.parent_object_id = c.object_id
  and fkc.parent_column_id = c.column_id
where fkc.constraint_object_id = @constraint_object_id
return @r
end

select distinct
  DropStmt = 'ALTER TABLE [' + ForeignKeys.ForeignTableSchema +
      '].[' + ForeignKeys.ForeignTableName +
      '] DROP CONSTRAINT [' + ForeignKeys.ForeignKeyName + '] '
,  CreateStmt = 'ALTER TABLE [' + ForeignKeys.ForeignTableSchema +
  '].[' + ForeignKeys.ForeignTableName +
  '] WITH CHECK ADD CONSTRAINT [' +  ForeignKeys.ForeignKeyName +
  '] FOREIGN KEY(' + dbo.fk_columns(constraint_object_id) + ')' +
  'REFERENCES [' + schema_name(sys.objects.schema_id) + '].[' +
  sys.objects.[name] + '] '
  + ' ON DELETE CASCADE'
 from sys.objects
  inner join sys.columns
    on (sys.columns.[object_id] = sys.objects.[object_id])
  inner join (
select sys.foreign_keys.[name] as ForeignKeyName
 ,schema_name(sys.objects.schema_id) as ForeignTableSchema
 ,sys.objects.[name] as ForeignTableName
 ,sys.columns.[name]  as ForeignTableColumn
 ,sys.foreign_keys.referenced_object_id as referenced_object_id
 ,sys.foreign_key_columns.referenced_column_id as referenced_column_id
 ,sys.foreign_keys.object_id as constraint_object_id
 from sys.foreign_keys
  inner join sys.foreign_key_columns
    on (sys.foreign_key_columns.constraint_object_id
      = sys.foreign_keys.[object_id])
  inner join sys.objects
    on (sys.objects.[object_id]
      = sys.foreign_keys.parent_object_id)
    inner join sys.columns
      on (sys.columns.[object_id]
        = sys.objects.[object_id])
       and (sys.columns.column_id
        = sys.foreign_key_columns.parent_column_id)
-- Uncomment this if you want to include only FKs that already
-- have a cascade constraint.
--       where (delete_referential_action_desc = 'CASCADE' or update_referential_action_desc = 'CASCADE')
) ForeignKeys
on (ForeignKeys.referenced_object_id = sys.objects.[object_id])
 and (ForeignKeys.referenced_column_id = sys.columns.column_id)
 where (sys.objects.[type] = 'U')
  and (sys.objects.[name] not in ('sysdiagrams'))

Vous pouvez également utiliser la requête pour aider supprimer ON DELETE CASCADE des FK qui en disposent actuellement.

Cela ne permet toujours pas de gérer le cas où les colonnes portent des noms différents dans les deux tables. Il faudrait définir une autre fonction définie par l'utilisateur pour cela.

Answer 3

Solution plus conforme aux normes :

;WITH CTE AS 
(
    SELECT  
         KCU1.CONSTRAINT_NAME AS FK_CONSTRAINT_NAME 
        ,KCU1.TABLE_SCHEMA AS FK_SCHEMA_NAME 
        ,KCU1.TABLE_NAME AS FK_TABLE_NAME 
        ,KCU1.COLUMN_NAME AS FK_COLUMN_NAME 
        ,KCU1.ORDINAL_POSITION AS FK_ORDINAL_POSITION 
        ,KCU2.CONSTRAINT_NAME AS REFERENCED_CONSTRAINT_NAME 
        ,KCU2.TABLE_SCHEMA AS REFERENCED_SCHEMA_NAME 
        ,KCU2.TABLE_NAME AS REFERENCED_TABLE_NAME 
        ,KCU2.COLUMN_NAME AS REFERENCED_COLUMN_NAME 
        ,KCU2.ORDINAL_POSITION AS REFERENCED_ORDINAL_POSITION 
    FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC 

    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU1 
        ON KCU1.CONSTRAINT_CATALOG = RC.CONSTRAINT_CATALOG  
        AND KCU1.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA 
        AND KCU1.CONSTRAINT_NAME = RC.CONSTRAINT_NAME 

    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU2 
        ON KCU2.CONSTRAINT_CATALOG = RC.UNIQUE_CONSTRAINT_CATALOG  
        AND KCU2.CONSTRAINT_SCHEMA = RC.UNIQUE_CONSTRAINT_SCHEMA 
        AND KCU2.CONSTRAINT_NAME = RC.UNIQUE_CONSTRAINT_NAME 
        AND KCU2.ORDINAL_POSITION = KCU1.ORDINAL_POSITION 
)

SELECT 
     FK_CONSTRAINT_NAME
    --,FK_SCHEMA_NAME
    --,FK_TABLE_NAME
    --,FK_COLUMN_NAME
    --,FK_ORDINAL_POSITION
    --,REFERENCED_CONSTRAINT_NAME
    --,REFERENCED_SCHEMA_NAME
    --,REFERENCED_TABLE_NAME
    --,REFERENCED_COLUMN_NAME
    --,REFERENCED_ORDINAL_POSITION

    ,
        'ALTER TABLE [' + FK_SCHEMA_NAME + ']' 
        + '.[' + FK_TABLE_NAME + '] ' 
        + 'DROP CONSTRAINT [' + FK_CONSTRAINT_NAME + ']; ' 
    AS DropStmt 

    ,
    'ALTER TABLE [' + FK_SCHEMA_NAME + ']' 
        + '.[' + FK_TABLE_NAME + '] ' + 
        + 'WITH CHECK ADD CONSTRAINT [' +  FK_CONSTRAINT_NAME + '] ' 
        + 'FOREIGN KEY([' + FK_COLUMN_NAME + ']) ' 
        + 'REFERENCES [' + REFERENCED_SCHEMA_NAME + '].[' + REFERENCED_TABLE_NAME + ']([' + REFERENCED_COLUMN_NAME + ']) ON DELETE CASCADE; ' 
    AS CreateStmt 

FROM CTE 

WHERE (1=1) 
/*
AND FK_TABLE_NAME IN 
(
     'T_SYS_Geschossrechte'
    ,'T_SYS_Gebaeuderechte'
    ,'T_SYS_Standortrechte'
)

AND REFERENCED_TABLE_NAME NOT LIKE 'T_AP_Ref_Mandant'
*/

ORDER BY  
     FK_TABLE_NAME
    ,FK_CONSTRAINT_NAME
    ,FK_COLUMN_NAME
    ,FK_ORDINAL_POSITION
    ,REFERENCED_CONSTRAINT_NAME
    ,REFERENCED_TABLE_NAME
    ,REFERENCED_COLUMN_NAME
    ,REFERENCED_ORDINAL_POSITION

Edit :
Étendu pour les clés étrangères multi-colonnes :

;WITH CTE AS 
( 
  SELECT  
         KCU1.CONSTRAINT_NAME AS FK_CONSTRAINT_NAME 
        ,KCU1.TABLE_SCHEMA AS FK_SCHEMA_NAME 
        ,KCU1.TABLE_NAME AS FK_TABLE_NAME 
        ,KCU1.COLUMN_NAME AS FK_COLUMN_NAME 
        ,KCU1.ORDINAL_POSITION AS FK_ORDINAL_POSITION 
        ,KCU2.CONSTRAINT_NAME AS REFERENCED_CONSTRAINT_NAME 
        ,KCU2.TABLE_SCHEMA AS REFERENCED_SCHEMA_NAME 
        ,KCU2.TABLE_NAME AS REFERENCED_TABLE_NAME 
        ,KCU2.COLUMN_NAME AS REFERENCED_COLUMN_NAME 
        ,KCU2.ORDINAL_POSITION AS REFERENCED_ORDINAL_POSITION 
    FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC 

    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU1 
        ON KCU1.CONSTRAINT_CATALOG = RC.CONSTRAINT_CATALOG  
        AND KCU1.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA 
        AND KCU1.CONSTRAINT_NAME = RC.CONSTRAINT_NAME 

    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU2 
        ON KCU2.CONSTRAINT_CATALOG = RC.UNIQUE_CONSTRAINT_CATALOG  
        AND KCU2.CONSTRAINT_SCHEMA = RC.UNIQUE_CONSTRAINT_SCHEMA 
        AND KCU2.CONSTRAINT_NAME = RC.UNIQUE_CONSTRAINT_NAME 
        AND KCU2.ORDINAL_POSITION = KCU1.ORDINAL_POSITION 
)
SELECT 
     FK_SCHEMA_NAME
    ,FK_TABLE_NAME
    ,FK_CONSTRAINT_NAME 
    --,FK_COLUMN_NAME
    --,REFERENCED_COLUMN_NAME

    ,
    'ALTER TABLE ' + QUOTENAME(FK_SCHEMA_NAME) + '.' + QUOTENAME(FK_TABLE_NAME) + ' ' 
      + 'DROP CONSTRAINT ' + QUOTENAME(FK_CONSTRAINT_NAME) + '; ' 
    AS DropStmt 

    ,
    'ALTER TABLE ' + QUOTENAME(FK_SCHEMA_NAME) + '.' + QUOTENAME(FK_TABLE_NAME) + ' 
    ADD CONSTRAINT ' + QUOTENAME(FK_CONSTRAINT_NAME) + ' 
    FOREIGN KEY('
    + 
        SUBSTRING 
        ( 
            (
                SELECT ', ' + QUOTENAME(FK.FK_COLUMN_NAME) AS [text()] 
                FROM CTE AS FK 
                WHERE FK.FK_CONSTRAINT_NAME = CTE.FK_CONSTRAINT_NAME
                AND FK.FK_SCHEMA_NAME = CTE.FK_SCHEMA_NAME
                AND FK.FK_TABLE_NAME = CTE.FK_TABLE_NAME 
                ORDER BY FK.FK_ORDINAL_POSITION
                FOR XML PATH, TYPE 
            ).value('.[1]', 'nvarchar(MAX)')
            ,3, 4000
        ) 
    + ') 
'
    + '    REFERENCES ' + QUOTENAME(REFERENCED_SCHEMA_NAME) + '.' + QUOTENAME(REFERENCED_TABLE_NAME) + '(' 
    + SUBSTRING 
      ( 
          (
              SELECT ', ' + QUOTENAME(Referenced.REFERENCED_COLUMN_NAME) AS [text()] 
              FROM CTE AS Referenced 
              WHERE Referenced.FK_CONSTRAINT_NAME = CTE.FK_CONSTRAINT_NAME
              AND Referenced.REFERENCED_SCHEMA_NAME = CTE.REFERENCED_SCHEMA_NAME
              AND Referenced.REFERENCED_TABLE_NAME = CTE.REFERENCED_TABLE_NAME
              ORDER BY Referenced.REFERENCED_ORDINAL_POSITION 
              FOR XML PATH, TYPE 
          ).value('.[1]', 'nvarchar(MAX)')
          , 3, 4000 
      )
    + ') 
    ON DELETE CASCADE 
; ' AS CreateStmt 

FROM CTE 

GROUP BY 
     FK_SCHEMA_NAME
    ,FK_TABLE_NAME
    ,FK_CONSTRAINT_NAME 

    ,REFERENCED_SCHEMA_NAME
    ,REFERENCED_TABLE_NAME

Et la version beaucoup plus simple pour PostGreSQL :

;WITH CTE AS 
( 
  SELECT  
         KCU1.CONSTRAINT_NAME AS FK_CONSTRAINT_NAME 
        ,KCU1.TABLE_SCHEMA AS FK_SCHEMA_NAME 
        ,KCU1.TABLE_NAME AS FK_TABLE_NAME 
        ,KCU1.COLUMN_NAME AS FK_COLUMN_NAME 
        ,KCU1.ORDINAL_POSITION AS FK_ORDINAL_POSITION 
        ,KCU2.CONSTRAINT_NAME AS REFERENCED_CONSTRAINT_NAME 
        ,KCU2.TABLE_SCHEMA AS REFERENCED_SCHEMA_NAME 
        ,KCU2.TABLE_NAME AS REFERENCED_TABLE_NAME 
        ,KCU2.COLUMN_NAME AS REFERENCED_COLUMN_NAME 
        ,KCU2.ORDINAL_POSITION AS REFERENCED_ORDINAL_POSITION 
    FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC 

    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU1 
        ON KCU1.CONSTRAINT_CATALOG = RC.CONSTRAINT_CATALOG  
        AND KCU1.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA 
        AND KCU1.CONSTRAINT_NAME = RC.CONSTRAINT_NAME 

    INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU2 
        ON KCU2.CONSTRAINT_CATALOG = RC.UNIQUE_CONSTRAINT_CATALOG  
        AND KCU2.CONSTRAINT_SCHEMA = RC.UNIQUE_CONSTRAINT_SCHEMA 
        AND KCU2.CONSTRAINT_NAME = RC.UNIQUE_CONSTRAINT_NAME 
        AND KCU2.ORDINAL_POSITION = KCU1.ORDINAL_POSITION 
)
SELECT 
     FK_SCHEMA_NAME
    ,FK_TABLE_NAME
    ,FK_CONSTRAINT_NAME 
    --,FK_COLUMN_NAME
    --,REFERENCED_COLUMN_NAME

    ,
    'ALTER TABLE ' || QUOTE_IDENT(FK_SCHEMA_NAME) || '.' || QUOTE_IDENT(FK_TABLE_NAME) || ' ' 
      || 'DROP CONSTRAINT ' || QUOTE_IDENT(FK_CONSTRAINT_NAME) || '; ' 
    AS DropStmt 

    ,
    'ALTER TABLE ' || QUOTE_IDENT(FK_SCHEMA_NAME) || '.' || QUOTE_IDENT(FK_TABLE_NAME) || ' 
    ADD CONSTRAINT ' || QUOTE_IDENT(FK_CONSTRAINT_NAME) || ' 
    FOREIGN KEY(' || string_agg(FK_COLUMN_NAME, ', ') || ') 
'
    || '    REFERENCES ' || QUOTE_IDENT(REFERENCED_SCHEMA_NAME) || '.' || QUOTE_IDENT(REFERENCED_TABLE_NAME) || '(' || string_agg(REFERENCED_COLUMN_NAME, ', ') || ') 
    ON DELETE CASCADE 
; ' AS CreateStmt 

FROM CTE 

GROUP BY 
     FK_SCHEMA_NAME
    ,FK_TABLE_NAME
    ,FK_CONSTRAINT_NAME 

    ,REFERENCED_SCHEMA_NAME
    ,REFERENCED_TABLE_NAME

Answer 4

Vous devrez modifier la table, supprimer les contraintes FK et les recréer :

C'est la syntaxe db2. SQLServer devrait être similaire

ALTER TABLE emp DROP CONSTRAINT fk_dept;

ALTER TABLE emp ADD CONSTRAINT fk_dept
FOREIGN KEY(dept_no)
REFERENCES dept(deptno)
ON DELETE CASCADE;

Vous pouvez écrire votre propre sp pour interroger la table système pour toutes les clés étrangères, les supprimer et les recréer. Pour ce faire, vous devrez utiliser un sql dynamique dans votre sp, où vous pourrez boucler sur les fk defn, les mettre dans un varchar et les ajouter/modifier pour inclure CASCADE, puis exécuter la stmt.

Answer 5

La réponse de @Andomar a fonctionné pour moi mais c'était un peu manuel - vous devez l'exécuter, puis copier les résultats et les exécuter. J'avais besoin de l'utiliser dans le cadre de ma configuration de test automatisée et j'avais donc besoin qu'elle soit exécutée automatiquement en une seule requête.

J'ai trouvé la solution suivante qui permet d'exécuter tout le SQL nécessaire pour modifier les contraintes de clé étrangère, puis de l'exécuter en une seule fois :

    IF Object_id('tempdb..#queriesForContraints') IS NOT NULL 
      BEGIN 
          DROP TABLE #queriesForContraints
      END 

    DECLARE @ignoreTablesCommaSeparated VARCHAR(1000)

    SELECT 'ALTER TABLE [' 
           + ForeignKeys.foreigntableschema + '].[' 
           + ForeignKeys.foreigntablename 
           + '] DROP CONSTRAINT [' 
           + ForeignKeys.foreignkeyname + ']; ' 
           + 'ALTER TABLE [' 
           + ForeignKeys.foreigntableschema + '].[' 
           + ForeignKeys.foreigntablename 
           + '] WITH CHECK ADD CONSTRAINT [' 
           + ForeignKeys.foreignkeyname 
           + '] FOREIGN KEY([' 
           + ForeignKeys.foreigntablecolumn 
           + ']) REFERENCES [' 
           + Schema_name(sys.objects.schema_id) + '].[' 
           + sys.objects.[name] + ']([' 
           + sys.columns.[name] 
           + ']) ON DELETE CASCADE; ' AS query
    INTO #queriesForContraints
    FROM   sys.objects 
           INNER JOIN sys.columns 
                   ON ( sys.columns.[object_id] = sys.objects.[object_id] ) 
           INNER JOIN (SELECT sys.foreign_keys.[name]                      AS 
                              ForeignKeyName, 
                              Schema_name(sys.objects.schema_id)           AS 
                  ForeignTableSchema, 
                              sys.objects.[name]                           AS 
                  ForeignTableName, 
                              sys.columns.[name]                           AS 
                  ForeignTableColumn, 
                              sys.foreign_keys.referenced_object_id        AS 
                  referenced_object_id, 
                              sys.foreign_key_columns.referenced_column_id AS 
                  referenced_column_id 
                       FROM   sys.foreign_keys 
                              INNER JOIN sys.foreign_key_columns 
                                      ON ( 
                              sys.foreign_key_columns.constraint_object_id = 
                              sys.foreign_keys.[object_id] ) 
                              INNER JOIN sys.objects 
                                      ON ( sys.objects.[object_id] = 
                                         sys.foreign_keys.parent_object_id ) 
                              INNER JOIN sys.columns 
                                      ON ( sys.columns.[object_id] = 
                                           sys.objects.[object_id] ) 
                                         AND ( sys.columns.column_id = 
    sys.foreign_key_columns.parent_column_id )) 
    ForeignKeys 
    ON ( ForeignKeys.referenced_object_id = sys.objects.[object_id] ) 
    AND ( ForeignKeys.referenced_column_id = sys.columns.column_id ) 
    WHERE  ( sys.objects.[type] = 'U' ) 
           AND ( sys.objects.[name] NOT IN ( 
                'sysdiagrams' --add more comma separated table names here if required
            ) ) 

    DECLARE @queryToRun NVARCHAR(MAX)

    SELECT  @queryToRun = STUFF(
            (SELECT query + ''
             FROM #queriesForContraints
             FOR XML PATH (''))
         , 1, 0, '')

    EXEC sp_executesql @statement = @queryToRun

    IF Object_id('tempdb..#queriesForContraints') IS NOT NULL 
      BEGIN 
          DROP TABLE #queriesForContraints
      END