SQL Server 2017

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CREATE TABLE A 
(
    [ID] VARCHAR(10) NOT NULL,
    CONSTRAINT [PK_A] PRIMARY KEY ([ID])
);

CREATE TABLE B 
(
    [ID] INT PRIMARY KEY, 
    [A_ID] VARCHAR(10) NOT NULL,
    CONSTRAINT [FK_B] FOREIGN KEY ([A_ID]) REFERENCES A([ID])
);

CREATE TABLE C 
(
    [ID] INT PRIMARY KEY, 
    [A_ID] VARCHAR(10) NOT NULL,
    CONSTRAINT [FK_C] FOREIGN KEY ([A_ID]) REFERENCES A([ID])
);
INSERT INTO A VALUES ('001'), ('010'), ('100');
INSERT INTO B VALUES (1, '001'), (2, '001'), (3, '010');
INSERT INTO C VALUES (4, '010'), (5, '100'), (6, '100');
9 rows affected

ALTER TABLE A ADD [ID_VB] VARBINARY(10);
ALTER TABLE B ADD [A_ID_VB] VARBINARY(10);
ALTER TABLE C ADD [A_ID_VB] VARBINARY(10);
BEGIN TRANSACTION
  UPDATE A SET [ID_VB] = CAST([ID] AS VARBINARY(10));
  UPDATE B SET [A_ID_VB] = CAST([A_ID] AS VARBINARY(10));
  UPDATE C SET [A_ID_VB] = CAST([A_ID] AS VARBINARY(10));
COMMIT TRANSACTION    
9 rows affected

ALTER TABLE B DROP CONSTRAINT [FK_B];
ALTER TABLE C DROP CONSTRAINT [FK_C];
ALTER TABLE A DROP CONSTRAINT [PK_A];
ALTER TABLE A DROP COLUMN [ID];
ALTER TABLE B DROP COLUMN [A_ID];
ALTER TABLE C DROP COLUMN [A_ID];
EXEC sp_rename 'A.ID_VB', 'ID', 'COLUMN';
EXEC sp_rename 'B.A_ID_VB', 'A_ID', 'COLUMN';
EXEC sp_rename 'C.A_ID_VB', 'A_ID', 'COLUMN';
Caution: Changing any part of an object name could break scripts and stored procedures.
Caution: Changing any part of an object name could break scripts and stored procedures.
Caution: Changing any part of an object name could break scripts and stored procedures.


ALTER TABLE A ALTER COLUMN [ID] VARBINARY(10) NOT NULL;
ALTER TABLE B ALTER COLUMN [A_ID] VARBINARY(10) NOT NULL;
ALTER TABLE C ALTER COLUMN [A_ID] VARBINARY(10) NOT NULL;
ALTER TABLE A ADD CONSTRAINT [PK_A] PRIMARY KEY ([ID]);
ALTER TABLE B ADD CONSTRAINT [FK_B] FOREIGN KEY ([A_ID]) REFERENCES A([ID]);
ALTER TABLE C ADD CONSTRAINT [FK_C] FOREIGN KEY ([A_ID]) REFERENCES A([ID]);
SELECT * FROM A;
SELECT * FROM B;
SELECT * FROM C;


ID


0x303031

0x303130

0x313030




ID
A_ID


1
0x303031

2
0x303031

3
0x303130




ID
A_ID


4
0x303130

5
0x313030

6
0x313030