SnowConvert: Transact Systemtabellen¶

Systemtabellen¶

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

Bekannte Probleme ¶

Es wurden keine Probleme gefunden.

SYS.FOREIGN_KEYS¶

Applies to

[x] SQL Server
[x] Azure Synapse Analytics

Bemerkung

Einige Teile des Ausgabecodes wurden aus Gründen der Übersichtlichkeit weggelassen.

Beschreibung¶

Enthält eine Zeile pro Objekt, die eine FOREIGN KEY-Einschränkung ist (SQLServer Dokumentation).

Die Spalten für FOREIGN KEY (sys.foreign_keys) sind die folgenden:

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

Die geerbten Spalten von sys.objects sind die folgenden:

Weitere Informationen finden Sie in der Dokumentation zu 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

Beachten Sie, dass es in diesem Fall für sys.foreign_keys keine Äquivalenz in Snowflake gibt. Aber die Gleichwertigkeit wird unter von sys.objects geerbten Spalten hergestellt.

Anwendbare Spaltenäquivalenz

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

Syntax in SQL Server

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

Copy

Syntax in Snowflake

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

Copy

Bemerkung

Da die Äquivalenz für die Systemfremdschlüssel die Katalogansicht in Snowflake für information_schema.table_constraints ist, ist es notwendig, den Typ der Einschränkung in einer zusätzlichen WHERE-Klausel zu definieren, um Fremdschlüsseleinschränkungen von anderen Einschränkungen zu unterscheiden.

Beispielhafte Quellcode-Muster¶

Um die folgenden Beispiele korrekt auszuführen (außer Mutser Nummer 3), müssen Sie die folgenden Anweisungen ausführen:

 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;

Copy

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';

Copy

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

Warnung

Die Ergebnisse unterscheiden sich aufgrund der Unterschiede bei den Spaltenobjekten und der fehlenden Äquivalenz. Das Ergebnis überprüft werden.

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';

Copy

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

Warnung

Diese Übersetzung muss möglicherweise überprüft werden, wenn der Name der Einschränkung von der Datenbank automatisch generiert und in der Abfrage verwendet wird. Weitere Informationen finden Sie im Abschnitt Bekannte Probleme.

3. Parent Object ID Case¶

In diesem Beispiel wurden eine Datenbank und ein Schema erstellt, um die Verarbeitung der Namen zur Erstellung unterschiedlicher und gleichwertiger Spalten zu veranschaulichen.

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

Warnung

Wenn der Name, der innerhalb der Funktion OBJECT_ID() kommt, kein gültiges Muster hat, wird er aufgrund von Beschränkungen bei der Verarbeitung von Sonderzeichen nicht konvertiert.

Warnung

Überprüfen Sie die Datenbank, die in Snowflake verwendet wird.

4. Type Column Case¶

Das ‚F‘ in SQL Server bedeutet „Fremdschlüssel“ und wird aufgrund der Validierung am Ende entfernt, um den Fremdschlüssel aus allen Tabelleneinschränkungen zu spezifizieren.

SQL Server¶

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

Copy

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';

Copy

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¶

Die Spalte ‚type_desc‘ wird aufgrund der Validierung am Ende zur Angabe des Fremdschlüssels aus allen Tabelleneinschränkungen entfernt.

SQL Server¶

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

Copy

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';

Copy

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;

Copy

The query produced no results.

Copy

Snowflake¶

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

Copy

The query produced no results.

Copy

7. Modify Date Column with DATEDIFF() Case¶

Das folgende Beispiel zeigt ein komplexeres Szenario, in dem sich die Spalten aus sys.foreign_keys (geerbt von sys.objects) innerhalb einer Funktion DATEDIFF befinden. In diesem Fall wird das Argument, das der zutreffenden Äquivalenz entspricht, in die entsprechende Spalte aus dem information.schema in Snowflake geändert.

SQL Server¶

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

Copy

The foreign keys altered in the last 30 days.

Copy

Snowflake¶

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

Copy

The foreign keys altered in the last 30 days.

Copy

8. Create Date Column Case¶

SQL Server¶

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

Copy

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

Copy

Snowflake¶

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

Copy

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

Copy

Warnung

Das Ergebnis kann sich ändern, wenn das Erstellungsdatum aufgrund der Zeit, zu der die Abfragen ausgeführt wurden, spezifisch ist. Es ist möglich, eine bestimmte Abfrage zu einem bestimmten Zeitpunkt in der Ursprungsdatenbank auszuführen und die Objekte dann zu einem anderen Zeitpunkt in den neuen Snowflake-Abfragen auszuführen.

9. Selected Columns Single Name Case¶

SQL Server¶

 SELECT name
FROM sys.foreign_keys;

Copy

name
FK_Name_Test

Snowflake¶

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

Copy

CONSTRAINT_NAME
FK_Name_Test

10. Selected Columns Qualified Name Case¶

SQL Server¶

 SELECT
    fk.name
FROM sys.foreign_keys AS fk;

Copy

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

Bekannte Probleme¶

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

Wenn es sich bei dem referenzierten Namen um einen automatisch aus der Datenbank generierten Namen handelt, ist es wahrscheinlich, dass Sie ihn überprüfen und den gewünschten Wert verwenden.

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

Da die Spalten aus sys.foreign_keys in Snowflake nicht vollständig äquivalent sind, können sich einige Ergebnisse aufgrund der Beschränkungen der Äquivalenz ändern.

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

Ausgehend von dem Namen, der die Funktion OBJECT_ID() erhält, wird die Verarbeitung dieses Namens eingeschränkt und von der Formatierung abhängig sein.

4. Name Column With OBJECT_NAME() Function Case¶

Da die Funktion OBJECT_NAME() noch nicht unterstützt wird, werden die mit dieser Funktion verbundenen Transformationen nicht unterstützt.

 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';

Copy

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.¶

Zugehörige EWIs¶

[SSC-EWI-0073](../../general/technical-documentation/issues-and-troubleshooting/conversion-issues/generalEWI. md#ssc-ewi-0073): Überprüfung der Funktionsäquivalenz ausstehend.