SnowConvert : Tables du système Transact¶

Tables du système¶

Transact-SQL	Snowflake SQL	Notes
SYS.ALL_VIEWS	INFORMATION_SCHEMA.VIEWS
SYS.ALL_COLUMNS	INFORMATION_SCHEMA.COLUMNS
SYS.COLUMNS	INFORMATION_SCHEMA.COLUMNS
SYS.OBJECTS	INFORMATION_SCHEMA.OBJECT_PRIVILEGES
SYS.PROCEDURES	INFORMATION_SCHEMA.PROCEDURES
SYS.SEQUENCES	INFORMATION_SCHEMA.SEQUENCES
SYS.ALL_OBJECTS	INFORMATION_SCHEMA.OBJECT_PRIVILEGES
ALL_PARAMETERS	Not supported
SYS.ALL_SQL_MODULES	Not supported
SYS.ALLOCATION_UNITS	Not supported
SYS.ASSEMBLY_MODULES	Not supported
SYS.CHECK_CONSTRAINTS	Not supported
SYS.COLUMN_STORE_DICTIONARIES	Not supported
SYS.COLUMN_STORE_ROW_GROUPS	Not supported
SYS.COLUMN_STORE_SEGMENTS	Not supported
SYS.COMPUTED_COLUMNS	Not supported
SYS.DEFAULT_CONSTRAINTS	Not supported
SYS.EVENTS	Not supported
SYS.EVENT_NOTIFICATIONS	Not supported
SYS.EVENT_NOTIFICATION_EVENT_TYPES	Not supported
SYS.EXTENDED_PROCEDURES	Not supported
SYS.EXTERNAL_LANGUAGE_FILES	Not supported
SYS.EXTERNAL_LANGUAGES	Not supported
SYS.EXTERNAL_LIBRARIES	Not supported
SYS.EXTERNAL_LIBRARY_FILES	Not supported
SYS.FOREIGN_KEYS	INFORMATION_SCHEMA.TABLE_CONSTRAINTS
SYS.FOREIGN_KEY_COLUMNS	Not supported
SYS.FUNCTION_ORDER_COLUMNS	Not supported
SYS.HASH_INDEXES	Not supported
SYS.INDEXES	Not supported
SYS.INDEX_COLUMNS	Not supported
SYS.INDEX_RESUMABLE_OPERATIONS	Not supported
SYS.INTERNAL_PARTITIONS	Not supported
SYS.INTERNAL_TABLES	Not supported
SYS.KEY_CONSTRAINTS	Not supported
SYS.MASKED_COLUMNS	Not supported
SYS.MEMORY_OPTIMIZED_TABLES_INTERNAL_ATTRIBUTES	Not supported
SYS.MODULE_ASSEMBLY_USAGES	Not supported
SYS.NUMBERED_PROCEDURES	Not supported
SYS.NUMBERED_PROCEDURE_PARAMETERS	Not supported
SYS.PARAMETERS	Not supported
SYS.PARTITIONS	Not supported
SYS.PERIODS	Not supported
SYS.SERVER_ASSEMBLY_MODULES	Not supported
SYS.SERVER_EVENTS	Not supported
SYS.SERVER_EVENTT_NOTIFICATIONS	Not supported
SYS.SERVER_SQL_MODULE	Not supported
SYS.SERVER_TRIGGERS	Not supported
SYS._SERVER_TRIGGER_EVENTS	Not supported
SYS.SQL_DEPENDENCIES	Not supported
SYS.SQL_EXPRESSION_DEPENDENCIES	Not supported
SYS.SQL_MODULES	Not supported
SYS.STATS	Not supported
SYS.STATS_COLUMNS	Not supported
SYS.SYNONYMS	Not supported
SYS.SYSTEM_COLUMNS	Not supported
SYS.SYSTEM_OBJECTS	Not supported
SYS.SYSTEM_PARAMETERS	Not supported
SYS.SYSTEM_SQL_MODULES"	Not supported

Problèmes connus ¶

Aucun problème n’a été constaté.

SYS.FOREIGN_KEYS¶

Applies to

[x] SQL Server
[x] Azure Synapse Analytics

Note

Certaines parties du code de sortie sont omises pour des raisons de clarté.

Description¶

Contient une ligne par objet qui est une contrainte FOREIGN KEY (documentation SQLServer).

Les colonnes de FOREIGN KEY (sys.foreign_keys) sont les suivantes :

Column name	Data type	Description	Has equivalent column in Snowflake
<Columns inherited from sys.objects>	-	For a list of columns that this view inherits, see sys.objects (Transact-SQL).	Partial
referenced_object_id	int	ID of the referenced object.	No
key_index_id	int	ID of the key index within the referenced object.	No
is_disabled	bit	FOREIGN KEY constraint is disabled.	No
is_not_for_replication	bit	FOREIGN KEY constraint was created by using the NOT FOR REPLICATION option.	No
is_not_trusted	bit	FOREIGN KEY constraint has not been verified by the system.	No
delete_referential_action	tinyint	The referential action that was declared for this FOREIGN KEY when a delete happens. See SQLServer Documentation.	No
delete_referential_action_desc	nvarchar(60)	Description of the referential action that was declared for this FOREIGN KEY when a delete occurs. See SQLServer Documentation.	No
update_referential_action	tinyint	The referential action that was declared for this FOREIGN KEY when an update happens. See SQLServer Documentation.	No
update_referential_action_desc	nvarchar(60)	Description of the referential action that was declared for this FOREIGN KEY when an update happens. See SQLServer Documentation.	No
is_system_named	bit	1 = Name was generated by the system. 0 = Name was supplied by the user.	No

Les colonnes héritées de sys.objects sont les suivantes :

Pour plus d’informations, consultez la documentation sys.objects.

Column name	Data type	Description	Has equivalent column in Snowflake
name	sysname	Object name.	Yes
object_id	int	Object identification number. Is unique within a database.	No
principal_id	int	ID of the individual owner, if different from the schema owner.	No
schema_id	int	ID of the schema that the object is contained in.	No
parent_object_id	int	ID of the object to which this object belongs.	No
type	char(2)	Object type	Yes
type_desc	nvarchar(60)	Description of the object type	Yes
create_date	datetime	Date the object was created.	Yes
modify_date	datetime	Date the object was last modified by using an ALTER statement.	Yes
is_ms_shipped	bit	Object is created by an internal SQL Server component.	No
is_published	bit	Object is created by an internal SQL Server component.	No
is_schema_published	bit	Only the schema of the object is published.	No

Remarquez que, dans ce casse, pour les sys.foreign_keys, il n’y a pas d’équivalence dans Snowflake. Mais, l’équivalence se fait sous les colonnes héritées de sys.objects.

Équivalence des colonnes applicables

SQLServer	Snowflake	Limitations	Applicable
name	CONSTRAINT_NAME	Names auto-generated by the database may be reviewed to the target Snowflake auto-generated name,	Yes
type	CONSTRAINT_TYPE	The type column has a variety of options. But, in this case, the support is only for the letter 'F' which represents the foreign keys.	No. Because of the extra validation to determine the foreign keys from all table constraints, it is not applicable.
type_desc	CONSTRAINT_TYPE	No limitions found.	No. Because of the extra validation to determine the foreign keys from all table constraints, it is not applicable.
create_date	CREATED	Data type differences.	Yes
modify_date	LAST_ALTERED	Data type differences.	Yes
parent_object_id	CONSTRAINT_CATALOG, CONSTRAINT_SCHEMA, TABLE_NAME	Columns are generated only for the cases that use the OBJECT_ID() function and, the name has a valid pattern.	Yes

Syntaxe dans SQL Server

 SELECT ('column_name' | * )
FROM sys.foreign_keys;

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Syntaxe dans Snowflake

 SELECT ('column_name' | * )
FROM information_schema.table_constraints 
WHERE CONSTRAINT_TYPE = 'FOREIGN KEY';

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Note

Comme l’équivalence pour les clés étrangères du système est la vue du catalogue dans Snowflake pour les contraintes d’information _schema.table_, il est nécessaire de définir le type de la contrainte dans une clause supplémentaire “WHERE” pour identifier les contraintes de clé étrangère par rapport aux autres contraintes.

Modèles d’échantillons de sources¶

Pour réaliser correctement les échantillons suivants (à l’exception du modèle numéro 3), il est nécessaire d’exécuter les instructions suivantes :

 CREATE TABLE Customers (
    CustomerID INT PRIMARY KEY,
    FirstName VARCHAR(50),
    LastName VARCHAR(50),
    Email VARCHAR(100)
);

CREATE TABLE Orders (
    OrderID INT PRIMARY KEY,
    CustomerID INT,
    OrderDate DATE,
    TotalAmount DECIMAL(10, 2),
    CONSTRAINT FK_Name_Test FOREIGN KEY (CustomerID) REFERENCES Customers(CustomerID)
);


INSERT INTO Customers (CustomerID, FirstName, LastName, Email)
VALUES
    (1, 'John', 'Doe', 'john.doe@example.com'),
    (2, 'Jane', 'Smith', 'jane.smith@example.com');

INSERT INTO Orders (OrderID, CustomerID, OrderDate, TotalAmount)
VALUES
    (101, 1, '2023-09-01', 100.50),
    (102, 1, '2023-09-02', 75.25),
    (103, 2, '2023-09-03', 50.00);

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 CREATE OR REPLACE TABLE Customers (
    CustomerID INT PRIMARY KEY,
    FirstName VARCHAR(50),
    LastName VARCHAR(50),
    Email VARCHAR(100)
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"transact"}}'
;

CREATE OR REPLACE TABLE Orders (
    OrderID INT PRIMARY KEY,
    CustomerID INT,
    OrderDate DATE,
    TotalAmount DECIMAL(10, 2),
       CONSTRAINT FK_Name_Test FOREIGN KEY (CustomerID) REFERENCES Customers (CustomerID)
   )
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},{"attributes":{"component":"transact"}}'
;

INSERT INTO Customers (CustomerID, FirstName, LastName, Email)
VALUES
    (1, 'John', 'Doe', 'john.doe@example.com'),
    (2, 'Jane', 'Smith', 'jane.smith@example.com');

INSERT INTO Orders (OrderID, CustomerID, OrderDate, TotalAmount)
VALUES
    (101, 1, '2023-09-01', 100.50),
    (102, 1, '2023-09-02', 75.25),
    (103, 2, '2023-09-03', 50.00);

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1. Simple Select Case¶

SQL Server¶

 SELECT *
FROM sys.foreign_keys;

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name	object_id	principal_id	schema_id	type	type_desc	create_date	modify_date	parent_object_id	is_ms_shipped	is_published	is_schema_published	referenced_object_id	key_index_id	is_disabled	is_not_for_replication	is_not_trusted	delete_referential_action	delete_referential_action_desc	update_referential_action	update_referential_action_desc	is_system_named
FK_Name_Test	1719677174	NULL	1	F	FOREIGN_KEY_CONSTRAINT	2023-09-11 22:20:04.160	2023-09-11 22:20:04.160	1687677060	false	true	false	1655676946	1	false	false		0	NO_ACTION	0	NO_ACTION	true

Snowflake¶

 SELECT *
FROM
INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
CONSTRAINT_TYPE = 'FOREIGN KEY';

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CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE	IS_DEFERRABLE	INITIALLY_DEFERRED	ENFORCED	COMMENT	CREATED	LAST_ALTERED	RELY
DBTEST	PUBLIC	FK_Name_Test	DATETEST	PUBLIC	ORDERS	FOREIGN KEY	NO	YES	NO	null	2023-09-11 15:23:51.969 -0700	2023-09-11 15:23:52.097 -0700	NO

Avertissement

Les résultats diffèrent en raison des différences dans les objets des colonnes et de l’équivalence manquante. Le résultat peut être vérifié.

2. Name Column Case¶

SQL Server¶

 SELECT * FROM sys.foreign_keys WHERE name = 'FK_Name_Test';

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name	object_id	principal_id	schema_id	type	type_desc	create_date	modify_date	parent_object_id	is_ms_shipped	is_published	is_schema_published	referenced_object_id	key_index_id	is_disabled	is_not_for_replication	is_not_trusted	delete_referential_action	delete_referential_action_desc	update_referential_action	update_referential_action_desc	is_system_named
FK_Name_Test	1719677174	NULL	1	F	FOREIGN_KEY_CONSTRAINT	2023-09-11 22:20:04.160	2023-09-11 22:20:04.160	1687677060	false	true	false	1655676946	1	false	false		0	NO_ACTION	0	NO_ACTION	true

Snowflake¶

 SELECT * FROM
INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
CONSTRAINT_NAME = 'FK_NAME_TEST'
AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE	IS_DEFERRABLE	INITIALLY_DEFERRED	ENFORCED	COMMENT	CREATED	LAST_ALTERED	RELY
DBTEST	PUBLIC	FK_Name_Test	DATETEST	PUBLIC	ORDERS	FOREIGN KEY	NO	YES	NO	null	2023-09-11 15:23:51.969 -0700	2023-09-11 15:23:52.097 -0700	NO

Avertissement

Cette traduction peut nécessiter une vérification si le nom de la contrainte est généré automatiquement par la base de données et utilisé dans la requête. Pour plus d’informations, consultez la section Problèmes connus.

3. Parent Object ID Case¶

Dans cet exemple, une base de données et un schéma ont été créés pour illustrer le traitement des noms afin de créer des colonnes différentes et équivalentes.

SQL Server¶

 use database_name_test
create schema schema_name_test

CREATE TABLE schema_name_test.Customers (
    CustomerID INT PRIMARY KEY,
    FirstName VARCHAR(50),
    LastName VARCHAR(50),
    Email VARCHAR(100)
);

CREATE TABLE schema_name_test.Orders (
    OrderID INT PRIMARY KEY,
    CustomerID INT,
    OrderDate DATE,
    TotalAmount DECIMAL(10, 2),
    CONSTRAINT FK_Name_Test FOREIGN KEY (CustomerID) REFERENCES schema_name_test.Customers(CustomerID)
);

INSERT INTO schema_name_test.Customers (CustomerID, FirstName, LastName, Email)
VALUES
    (1, 'John', 'Doe', 'john.doe@example.com'),
    (2, 'Jane', 'Smith', 'jane.smith@example.com');

INSERT INTO schema_name_test.Orders (OrderID, CustomerID, OrderDate, TotalAmount)
VALUES
    (101, 1, '2023-09-01', 100.50),
    (102, 1, '2023-09-02', 75.25),
    (103, 2, '2023-09-03', 50.00);

SELECT * FROM sys.foreign_keys WHERE name = 'FK_Name_Test' AND parent_object_id = OBJECT_ID(N'database_name_test.schema_name_test.Orders')

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name	object_id	principal_id	schema_id	type	type_desc	create_date	modify_date	parent_object_id	is_ms_shipped	is_published	is_schema_published	referenced_object_id	key_index_id	is_disabled	is_not_for_replication	is_not_trusted	delete_referential_action	delete_referential_action_desc	update_referential_action	update_referential_action_desc	is_system_named
FK_Name_Test	1719677174	NULL	1	F	FOREIGN_KEY_CONSTRAINT	2023-09-11 22:20:04.160	2023-09-11 22:20:04.160	1687677060	false	true	false	1655676946	1	false	false		0	NO_ACTION	0	NO_ACTION	true

Snowflake¶

 USE DATABASE database_name_test;

CREATE OR REPLACE SCHEMA schema_name_test
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"transact"}}'
;

CREATE OR REPLACE TABLE schema_name_test.Customers (
    CustomerID INT PRIMARY KEY,
    FirstName VARCHAR(50),
    LastName VARCHAR(50),
    Email VARCHAR(100)
)
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"transact"}}'
;

CREATE OR REPLACE TABLE schema_name_test.Orders (
    OrderID INT PRIMARY KEY,
    CustomerID INT,
    OrderDate DATE,
    TotalAmount DECIMAL(10, 2),
       CONSTRAINT FK_Name_Test FOREIGN KEY (CustomerID) REFERENCES schema_name_test.Customers (CustomerID)
   )
COMMENT = '{"origin":"sf_sc","name":"snowconvert","version":{"major":1, "minor":0},"attributes":{"component":"transact"}}'
;

INSERT INTO schema_name_test.Customers (CustomerID, FirstName, LastName, Email)
VALUES
    (1, 'John', 'Doe', 'john.doe@example.com'),
    (2, 'Jane', 'Smith', 'jane.smith@example.com');

INSERT INTO schema_name_test.Orders (OrderID, CustomerID, OrderDate, TotalAmount)
VALUES
    (101, 1, '2023-09-01', 100.50),
    (102, 1, '2023-09-02', 75.25),
    (103, 2, '2023-09-03', 50.00);

SELECT * FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    CONSTRAINT_NAME = 'FK_NAME_TEST'
    AND CONSTRAINT_CATALOG = 'DATABASE_NAME_TEST'
    AND CONSTRAINT_SCHEMA = 'SCHEMA_NAME_TEST'
    AND TABLE_NAME = 'ORDERS'
    AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE	IS_DEFERRABLE	INITIALLY_DEFERRED	ENFORCED	COMMENT	CREATED	LAST_ALTERED	RELY
DATABASE_NAME_TEST	SCHEMA_NAME_TEST	FK_Name_Test	DATABASE_NAME_TEST	SCHEMA_NAME_TEST	ORDERS	FOREIGN KEY	NO	YES	NO	null	2023-09-11 15:23:51.969 -0700	2023-09-11 15:23:52.097 -0700	NO

Avertissement

Si le nom entrant dans la fonction OBJECT_ID() n’a pas de modèle valide, il ne sera pas converti en raison des limites de traitement des noms sur les caractères spéciaux.

Avertissement

Passez en revue la base de données utilisée dans Snowflake.

4. Type Column Case¶

Le « F » dans SQL Server signifie « Foreign Key » (clé étrangère) et il est supprimé en raison de la validation à la fin pour spécifier la clé étrangère à partir de toutes les contraintes de la table.

SQL Server¶

 SELECT * FROM sys.foreign_keys WHERE type = 'F';

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name	object_id	principal_id	schema_id	type	type_desc	create_date	modify_date	parent_object_id	is_ms_shipped	is_published	is_schema_published	referenced_object_id	key_index_id	is_disabled	is_not_for_replication	is_not_trusted	delete_referential_action	delete_referential_action_desc	update_referential_action	update_referential_action_desc	is_system_named
FK_Name_Test	1719677174	NULL	3	F	FOREIGN_KEY_CONSTRAINT	2023-09-11 22:20:04.160	2023-09-11 22:20:04.160	1687677060	false	true	false	1655676946	1	false	false		0	NO_ACTION	0	NO_ACTION	true

Snowflake¶

 SELECT * FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    type = 'F' AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE	IS_DEFERRABLE	INITIALLY_DEFERRED	ENFORCED	COMMENT	CREATED	LAST_ALTERED	RELY
DBTEST	PUBLIC	FK_Name_Test	DATETEST	PUBLIC	ORDERS	FOREIGN KEY	NO	YES	NO	null	2023-09-11 15:23:51.969 -0700	2023-09-11 15:23:52.097 -0700	NO

5. Type Desc Column Case¶

La colonne « type_desc » est supprimée en raison de la validation à la fin pour spécifier la clé étrangère à partir de toutes les contraintes de la table.

SQL Server¶

 SELECT
    * 
FROM
    sys.foreign_keys 
WHERE 
    type_desc = 'FOREIGN_KEY_CONSTRAINT';

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name	object_id	principal_id	schema_id	type	type_desc	create_date	modify_date	parent_object_id	is_ms_shipped	is_published	is_schema_published	referenced_object_id	key_index_id	is_disabled	is_not_for_replication	is_not_trusted	delete_referential_action	delete_referential_action_desc	update_referential_action	update_referential_action_desc	is_system_named
FK_Name_Test	1719677174	NULL	3	F	FOREIGN_KEY_CONSTRAINT	2023-09-11 22:20:04.160	2023-09-11 22:20:04.160	1687677060	false	true	false	1655676946	1	false	false		0	NO_ACTION	0	NO_ACTION	true

Snowflake¶

 SELECT
    *
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    type_desc = 'FOREIGN_KEY_CONSTRAINT' AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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CONSTRAINT_CATALOG	CONSTRAINT_SCHEMA	CONSTRAINT_NAME	TABLE_CATALOG	TABLE_SCHEMA	TABLE_NAME	CONSTRAINT_TYPE	IS_DEFERRABLE	INITIALLY_DEFERRED	ENFORCED	COMMENT	CREATED	LAST_ALTERED	RELY
DBTEST	PUBLIC	FK_Name_Test	DATETEST	PUBLIC	ORDERS	FOREIGN KEY	NO	YES	NO	null	2023-09-11 15:23:51.969 -0700	2023-09-11 15:23:52.097 -0700	NO

6. Modify Date Column Simple Case¶

SQL Server¶

 SELECT *
FROM sys.foreign_keys
WHERE modify_date = CURRENT_TIMESTAMP;

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The query produced no results.

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Snowflake¶

 SELECT *
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    LAST_ALTERED = CURRENT_TIMESTAMP()
    AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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The query produced no results.

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7. Modify Date Column with DATEDIFF() Case¶

L’exemple suivant montre un scénario plus complexe dans lequel les colonnes de sys.foreign_keys (héritées de sys.objects) se trouvent à l’intérieur d’une fonction DATEDIFF. Dans ce cas, l’argument correspondant à l’équivalence applicable est remplacé par la colonne correspondante du schéma information.schema dans Snowflake.

SQL Server¶

 SELECT *
FROM sys.foreign_keys
WHERE DATEDIFF(DAY, modify_date, GETDATE()) <= 30;

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The foreign keys altered in the last 30 days.

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Snowflake¶

 SELECT *
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    DATEDIFF(DAY, LAST_ALTERED, CURRENT_TIMESTAMP() :: TIMESTAMP) <= 30
    AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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The foreign keys altered in the last 30 days.

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8. Create Date Column Case¶

SQL Server¶

 SELECT *
FROM sys.foreign_keys
WHERE create_date = '2023-09-12 14:36:38.060';

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The foreign keys that were created on the specified date and time.

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Snowflake¶

 SELECT *
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    CREATED = '2023-09-12 14:36:38.060'
    AND CONSTRAINT_TYPE = 'FOREIGN KEY';

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The foreign keys that were created on the specified date and time.

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Avertissement

Le résultat peut changer si la date de création est spécifique en raison de l’heure à laquelle les requêtes ont été exécutées. Il est possible d’exécuter une requête spécifique à un moment donné sur la base de données d’origine, puis d’exécuter les objets à un autre moment dans les nouvelles requêtes Snowflake.

9. Selected Columns Single Name Case¶

SQL Server¶

 SELECT name
FROM sys.foreign_keys;

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name
FK_Name_Test

Snowflake¶

 SELECT
    CONSTRAINT_NAME
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    CONSTRAINT_TYPE = 'FOREIGN KEY';

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CONSTRAINT_NAME
FK_Name_Test

10. Selected Columns Qualified Name Case¶

SQL Server¶

 SELECT
    fk.name
FROM sys.foreign_keys AS fk;

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name
FK_Name_Test

Snowflake¶

 SELECT
    fk.CONSTRAINT_NAME
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS fk
WHERE
    CONSTRAINT_TYPE = 'FOREIGN KEY';

Copy

CONSTRAINT_NAME
FK_Name_Test

Problèmes connus¶

1. The “name” column may not show a correct output if the constraint does not have a user-created name¶

Si la référence est un nom généré automatiquement à partir de la base de données, il est probable qu’elle soit révisée et que la valeur souhaitée soit utilisée.

2. When selecting columns, there is a limitation that depends on the applicable columns that are equivalent in Snowflake¶

Les colonnes de sys.foreign_keys n’étant pas complètement équivalentes dans Snowflake, certains résultats peuvent changer en raison des limites d’équivalence.

3. The OBJECT_ID() function may have a valid pattern to be processed or the database, schema or table could not be extracted¶

En fonction du nom qui reçoit la fonction OBJECT_ID(), le traitement de ce nom sera limité et dépendra du formatage.

4. Name Column With OBJECT_NAME() Function Case¶

La fonction OBJECT_NAME() n’étant pas encore prise en charge, les transformations liées à cette fonction ne sont pas prises en charge.

 SELECT name AS ForeignKeyName,
       OBJECT_NAME(parent_object_id) AS ReferencingTable,
       OBJECT_NAME(referenced_object_id) AS ReferencedTable
FROM sys.foreign_keys;

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 SELECT
    name AS ForeignKeyName,
    !!!RESOLVE EWI!!! /*** SSC-EWI-0073 - PENDING FUNCTIONAL EQUIVALENCE REVIEW FOR 'OBJECT_NAME' NODE ***/!!!
    OBJECT_NAME(parent_object_id) AS ReferencingTable,
    !!!RESOLVE EWI!!! /*** SSC-EWI-0073 - PENDING FUNCTIONAL EQUIVALENCE REVIEW FOR 'OBJECT_NAME' NODE ***/!!!
    OBJECT_NAME(referenced_object_id) AS ReferencedTable
FROM
    INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE
    CONSTRAINT_TYPE = 'FOREIGN KEY';

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5. SCHEMA_NAME() and TYPE_NAME() functions are also not supported yet.¶

6. Different Join statement types may be not supported if the system table is not supported.¶

7. Cases with JOIN statements are not supported.¶

8. Names with alias AS are not supported.¶

EWIs connexes¶

SSC-EWI-0073 : En attente de l’examen de l’équivalence fonctionnelle.