Bagaimana untuk Menghasilkan Skrip SQL CREATE untuk Jadual Sedia Ada?

Cara Menjana SQL Mencipta Skrip untuk Jadual Sedia Ada dengan Pertanyaan

Soalan ini berkaitan dengan penjanaan skrip SQL CREATE untuk jadual yang sudah wujud. Walaupun sintaks yang diberikan menangani tugas ini dengan tepat, beberapa penambahbaikan boleh dibuat pada respons.

Tindak Balas Yang Dipertingkat:

Mungkin ini berguna untuk anda. Skrip ini menjana indeks, kunci asing (FK), kunci utama (PK) dan struktur biasa untuk mana-mana jadual. Skrip terdiri daripada bahagian pertanyaan yang mengumpulkan maklumat jadual dan menggabungkan pernyataan CREATE yang sesuai.

Sebagai contoh, mempertimbangkan definisi jadual berikut:

CREATE TABLE [dbo].[WorkOut]
(
[WorkOutID] [bigint] IDENTITY(1,1) NOT NULL,
[TimeSheetDate] [datetime] NOT NULL,
[DateOut] [datetime] NOT NULL,
[EmployeeID] [int] NOT NULL,
[IsMainWorkPlace] [bit] NOT NULL,
[DepartmentUID] [uniqueidentifier] NOT NULL,
[WorkPlaceUID] [uniqueidentifier] NULL,
[TeamUID] [uniqueidentifier] NULL,
[WorkShiftCD] [nvarchar](10) NULL,
[WorkHours] [real] NULL,
[AbsenceCode] [varchar](25) NULL,
[PaymentType] [char](2) NULL,
[CategoryID] [int] NULL,
[Year] AS (datepart(year,[TimeSheetDate])),
CONSTRAINT [PK_WorkOut] PRIMARY KEY CLUSTERED ([WorkOutID] ASC)
) ON [PRIMARY]

ALTER TABLE [dbo].[WorkOut] ADD  CONSTRAINT [DF__WorkOut__IsMainW__2C1E8537] DEFAULT ((1)) FOR [IsMainWorkPlace]

ALTER TABLE [dbo].[WorkOut] WITH CHECK ADD CONSTRAINT [FK_WorkOut_Employee_EmployeeID] FOREIGN KEY([EmployeeID]) REFERENCES [dbo].[Employee] ([EmployeeID])

ALTER TABLE [dbo].[WorkOut] CHECK CONSTRAINT [FK_WorkOut_Employee_EmployeeID]

Skrip pertanyaan boleh digunakan untuk menjana pernyataan DDL untuk mencipta semula jadual.

Declare @table_name SYSNAME = 'dbo.WorkOut'

Declare
@object_name SYSNAME,
@object_id INT

SELECT
@object_name = '[' + s.name + '].[' + o.name + ']',
@object_id = o.[object_id]
FROM sys.objects o WITH (NOWAIT)
JOIN sys.schemas s WITH (NOWAIT) ON o.[schema_id] = s.[schema_id]
WHERE s.name + '.' + o.name = @table_name
AND o.[type] = 'U'
AND o.is_ms_shipped = 0

DECLARE @SQL NVARCHAR(MAX) = ''

;WITH index_column AS
(
SELECT
ic.[object_id],
ic.index_id,
ic.is_descending_key,
ic.is_included_column,
c.name
FROM sys.index_columns ic WITH (NOWAIT)
JOIN sys.columns c WITH (NOWAIT) ON ic.[object_id] = c.[object_id] AND ic.column_id = c.column_id
WHERE ic.[object_id] = @object_id
),
fk_columns AS
(
SELECT
k.constraint_object_id,
cname = c.name,
rcname = rc.name
FROM sys.foreign_key_columns k WITH (NOWAIT)
JOIN sys.columns rc WITH (NOWAIT) ON rc.[object_id] = k.referenced_object_id AND rc.column_id = k.referenced_column_id
JOIN sys.columns c WITH (NOWAIT) ON c.[object_id] = k.parent_object_id AND c.column_id = k.parent_column_id
WHERE k.parent_object_id = @object_id
)
SELECT @SQL = 'CREATE TABLE ' + @object_name + CHAR(13) + '(' + CHAR(13) + STUFF((
SELECT CHAR(9) + ', [' + c.name + '] ' +
CASE WHEN c.is_computed = 1
THEN 'AS ' + cc.[definition]
ELSE UPPER(tp.name) +
CASE WHEN tp.name IN ('varchar', 'char', 'varbinary', 'binary', 'text')
THEN '(' + CASE WHEN c.max_length = -1 THEN 'MAX' ELSE CAST(c.max_length AS VARCHAR(5)) END + ')'
WHEN tp.name IN ('nvarchar', 'nchar', 'ntext')
THEN '(' + CASE WHEN c.max_length = -1 THEN 'MAX' ELSE CAST(c.max_length / 2 AS VARCHAR(5)) END + ')'
WHEN tp.name IN ('datetime2', 'time2', 'datetimeoffset')
THEN '(' + CAST(c.scale AS VARCHAR(5)) + ')'
WHEN tp.name IN ('decimal', 'numeric')
THEN '(' + CAST(c.[precision] AS VARCHAR(5)) + ',' + CAST(c.scale AS VARCHAR(5)) + ')'
ELSE ''
END +
CASE WHEN c.collation_name IS NOT NULL THEN ' COLLATE ' + c.collation_name ELSE '' END +
CASE WHEN c.is_nullable = 1 THEN ' NULL' ELSE ' NOT NULL' END +
CASE WHEN dc.[definition] IS NOT NULL THEN ' DEFAULT' + dc.[definition] ELSE '' END +
CASE WHEN ic.is_identity = 1 THEN ' IDENTITY(' + CAST(ISNULL(ic.seed_value, '0') AS CHAR(1)) + ',' + CAST(ISNULL(ic.increment_value, '1') AS CHAR(1)) + ')' ELSE '' END
END + CHAR(13)
FROM sys.columns c WITH (NOWAIT)
JOIN sys.types tp WITH (NOWAIT) ON c.user_type_id = tp.user_type_id
LEFT JOIN sys.computed_columns cc WITH (NOWAIT) ON c.[object_id] = cc.[object_id] AND c.column_id = cc.column_id
LEFT JOIN sys.default_constraints dc WITH (NOWAIT) ON c.default_object_id != 0 AND c.[object_id] = dc.parent_object_id AND c.column_id = dc.parent_column_id
LEFT JOIN sys.identity_columns ic WITH (NOWAIT) ON c.is_identity = 1 AND c.[object_id] = ic.[object_id] AND c.column_id = ic.column_id
WHERE c.[object_id] = @object_id
ORDER BY c.column_id
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, CHAR(9) + ' ')
+ ISNULL((SELECT CHAR(9) + ', CONSTRAINT [' + k.name + '] PRIMARY KEY (' +
(SELECT STUFF((
SELECT ', [' + c.name + '] ' + CASE WHEN ic.is_descending_key = 1 THEN 'DESC' ELSE 'ASC' END
FROM sys.index_columns ic WITH (NOWAIT)
JOIN sys.columns c WITH (NOWAIT) ON c.[object_id] = ic.[object_id] AND c.column_id = ic.column_id
WHERE ic.is_included_column = 0
AND ic.[object_id] = k.parent_object_id
AND ic.index_id = k.unique_index_id
FOR XML PATH(N''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, ''))
+ ')' + CHAR(13)
FROM sys.key_constraints k WITH (NOWAIT)
WHERE k.parent_object_id = @object_id
AND k.[type] = 'PK'), '') + ')' + CHAR(13)
+ ISNULL((SELECT (
SELECT CHAR(13) +
'ALTER TABLE ' + @object_name + ' WITH'
+ CASE WHEN fk.is_not_trusted = 1
THEN ' NOCHECK'
ELSE ' CHECK'
END +
' ADD CONSTRAINT [' + fk.name + '] FOREIGN KEY('
+ STUFF((
SELECT ', [' + k.cname + ']'
FROM fk_columns k
WHERE k.constraint_object_id = fk.[object_id]
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, '')
+ ')' +
' REFERENCES [' + SCHEMA_NAME(ro.[schema_id]) + '].[' + ro.name + '] ('
+ STUFF((
SELECT ', [' + k.rcname + ']'
FROM fk_columns k
WHERE k.constraint_object_id = fk.[object_id]
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 2, '')
+ ')'
+ CASE
WHEN fk.delete_referential_action = 1 THEN ' ON DELETE CASCADE'
WHEN fk.delete_referential_action = 2 THEN ' ON DELETE SET NULL'
WHEN fk.delete_referential_action = 3 THEN ' ON DELETE SET DEFAULT'
ELSE ''
END
+ CASE

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