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Kopieren Sie Indizes programmgesteuert von einer Tabelle in eine andere in SQL Server

Das habe ich mir ausgedacht. Es funktioniert für mich und kopiert alles, was mir wichtig ist.

CREATE PROCEDURE [dbo].[spCloneTableStructure]
    @SourceSchema nvarchar(255),
    @SourceTable nvarchar(255),
    @DestinationSchema nvarchar(255),
    @DestinationTable nvarchar(255),
    @RecreateIfExists bit = 0
AS
BEGIN
    /*
        Clones an existing table to another table (without data)
        Optionally drops and re-creates target table
        Copies:
            * Structure
            * Primary key
            * Indexes (including ASC/DESC, included columns, filters)
            * Constraints (and unique constraints)

        DOES NOT copy:
            * Triggers
            * File groups
            * Probably a lot of other things

        Note: Assumes that you name (unique) constraints with the table name in it (in order to not duplicate constraint names)
    */
    SET NOCOUNT ON;

    BEGIN TRANSACTION

    --drop the table
    if EXISTS (SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_SCHEMA = @DestinationSchema AND TABLE_NAME = @DestinationTable)
    BEGIN
        if @RecreateIfExists = 1
        BEGIN
            exec('DROP TABLE [' + @DestinationSchema + '].[' + @DestinationTable + ']')
        END
        ELSE
            RETURN
    END

    --create the table
    exec('SELECT TOP (0) * INTO [' + @DestinationSchema + '].[' + @DestinationTable + '] FROM [' + @SourceSchema + '].[' + @SourceTable + ']')

    DECLARE @PKSchema nvarchar(255), @PKName nvarchar(255)
    SELECT TOP 1 @PKSchema = CONSTRAINT_SCHEMA, @PKName = CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS WHERE TABLE_SCHEMA = @SourceSchema AND TABLE_NAME = @SourceTable AND CONSTRAINT_TYPE = 'PRIMARY KEY'

    --create primary key
    IF NOT @PKSchema IS NULL AND NOT @PKName IS NULL
    BEGIN
        DECLARE @PKColumns nvarchar(MAX)
        SET @PKColumns = ''

        SELECT @PKColumns = @PKColumns + '[' + COLUMN_NAME + '],'
            FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE 
            where TABLE_NAME = @SourceTable and TABLE_SCHEMA = @SourceSchema AND CONSTRAINT_SCHEMA = @PKSchema AND CONSTRAINT_NAME= @PKName
            ORDER BY ORDINAL_POSITION

        SET @PKColumns = LEFT(@PKColumns, LEN(@PKColumns) - 1)

        exec('ALTER TABLE [' + @DestinationSchema + '].[' + @DestinationTable + '] ADD  CONSTRAINT [PK_' + @DestinationTable + '] PRIMARY KEY CLUSTERED (' + @PKColumns + ')');
    END

    --create other indexes
    DECLARE @IndexId int, @IndexName nvarchar(255), @IsUnique bit, @IsUniqueConstraint bit, @FilterDefinition nvarchar(max)

    DECLARE indexcursor CURSOR FOR
    SELECT index_id, name, is_unique, is_unique_constraint, filter_definition FROM sys.indexes WHERE type = 2 and object_id = object_id('[' + @SourceSchema + '].[' + @SourceTable + ']')
    OPEN indexcursor;
    FETCH NEXT FROM indexcursor INTO @IndexId, @IndexName, @IsUnique, @IsUniqueConstraint, @FilterDefinition;
    WHILE @@FETCH_STATUS = 0
       BEGIN
            DECLARE @Unique nvarchar(255)
            SET @Unique = CASE WHEN @IsUnique = 1 THEN ' UNIQUE ' ELSE '' END

            DECLARE @KeyColumns nvarchar(max), @IncludedColumns nvarchar(max)
            SET @KeyColumns = ''
            SET @IncludedColumns = ''

            select @KeyColumns = @KeyColumns + '[' + c.name + '] ' + CASE WHEN is_descending_key = 1 THEN 'DESC' ELSE 'ASC' END + ',' from sys.index_columns ic
            inner join sys.columns c ON c.object_id = ic.object_id and c.column_id = ic.column_id
            where index_id = @IndexId and ic.object_id = object_id('[' + @SourceSchema + '].[' + @SourceTable + ']') and key_ordinal > 0
            order by index_column_id

            select @IncludedColumns = @IncludedColumns + '[' + c.name + '],' from sys.index_columns ic
            inner join sys.columns c ON c.object_id = ic.object_id and c.column_id = ic.column_id
            where index_id = @IndexId and ic.object_id = object_id('[' + @SourceSchema + '].[' + @SourceTable + ']') and key_ordinal = 0
            order by index_column_id

            IF LEN(@KeyColumns) > 0
                SET @KeyColumns = LEFT(@KeyColumns, LEN(@KeyColumns) - 1)

            IF LEN(@IncludedColumns) > 0
            BEGIN
                SET @IncludedColumns = ' INCLUDE (' + LEFT(@IncludedColumns, LEN(@IncludedColumns) - 1) + ')'
            END

            IF @FilterDefinition IS NULL
                SET @FilterDefinition = ''
            ELSE
                SET @FilterDefinition = 'WHERE ' + @FilterDefinition + ' '

            if @IsUniqueConstraint = 0
                exec('CREATE ' + @Unique + ' NONCLUSTERED INDEX [' + @IndexName + '] ON [' + @DestinationSchema + '].[' + @DestinationTable + '] (' + @KeyColumns + ')' + @IncludedColumns + @FilterDefinition)
            ELSE
                BEGIN
                    SET @IndexName = REPLACE(@IndexName, @SourceTable, @DestinationTable)
                    exec('ALTER TABLE [' + @DestinationSchema + '].[' + @DestinationTable + '] ADD  CONSTRAINT [' + @IndexName + '] UNIQUE NONCLUSTERED (' + @KeyColumns + ')');
                END

            FETCH NEXT FROM indexcursor INTO @IndexId, @IndexName, @IsUnique, @IsUniqueConstraint, @FilterDefinition;
       END;
    CLOSE indexcursor;
    DEALLOCATE indexcursor;

    --create constraints
    DECLARE @ConstraintName nvarchar(max), @CheckClause nvarchar(max)
    DECLARE constraintcursor CURSOR FOR
        SELECT REPLACE(c.CONSTRAINT_NAME, @SourceTable, @DestinationTable), CHECK_CLAUSE from INFORMATION_SCHEMA.CONSTRAINT_TABLE_USAGE t
        INNER JOIN INFORMATION_SCHEMA.CHECK_CONSTRAINTS c ON c.CONSTRAINT_SCHEMA = TABLE_SCHEMA AND c.CONSTRAINT_NAME = t.CONSTRAINT_NAME
         WHERE TABLE_SCHEMA = @SourceSchema AND TABLE_NAME = @SourceTable
    OPEN constraintcursor;
    FETCH NEXT FROM constraintcursor INTO @ConstraintName, @CheckClause;
    WHILE @@FETCH_STATUS = 0
       BEGIN
            exec('ALTER TABLE [' + @DestinationSchema + '].[' + @DestinationTable + '] WITH CHECK ADD  CONSTRAINT [' + @ConstraintName + '] CHECK ' + @CheckClause)
            exec('ALTER TABLE [' + @DestinationSchema + '].[' + @DestinationTable + '] CHECK CONSTRAINT [' + @ConstraintName + ']')
            FETCH NEXT FROM constraintcursor INTO @ConstraintName, @CheckClause;
       END;
    CLOSE constraintcursor;
    DEALLOCATE constraintcursor;

    COMMIT TRANSACTION
END