从 SQL Server 2008 中的数组创建动态查询列表

Question

我从Fill dynamic array with values from an array 拆分了这个问题。下面是我现在拥有的实际代码。

首先是动态代码，其次是我希望动态代码输出的 3 个示例查询（但它没有输出）。我收到一个错误Invalid column name "field"，或者当我将field 更改为#tmp_auditlog_fields.field 时，出现the column "field" cannot be bound 的错误。后一个错误可能是由于我没有加入任何表，但我不知道要加入表的字段，因为#tmp_auditlogs_fields 只不过是一个创建一堆查询的数组，与数据库中的任何真实数据无关.

如何获得所需的输出？非常感谢任何帮助:-)

-- dynamic code

create table #tmp_auditlog_fields (
  id int identity(1,1),
  field varchar(255),
  details varchar(255)
);

insert into #tmp_auditlog_fields (field, details) values
    ('a', 'foo'),
    ('b', 'bar'),
    ('c', 'baz'),
;

declare @sql nvarchar(max);
declare @cnt int, @i int = 1;

select @cnt = max(id) from #tmp_auditlog_fields;

while @i <= @cnt
    begin
        select @sql = 
            'select t.objectID, t.DocID as ' + field + 
            ' into #tmp_auditlog_' + field + 
            ' from #tmp_auditlog_subselection t where Details like ' + 
            details FROM  tmp_auditlog_fields WHERE id = @i
        exec sp_executesql @sql
        select @i = @i + 1
    end 
;

-- example queries

select t.ObjectID, t.DocID as a 
into #tmp_auditlog_a from #tmp_auditlog_subselection t
where Details like 'foo';

select t.ObjectID, t.DocID as b 
into #tmp_auditlog_b from #tmp_auditlog_subselection t
where Details like 'bar';

select t.ObjectID, t.DocID as c 
into #tmp_auditlog_c from #tmp_auditlog_subselection t
where Details like 'baz';

SQL Fiddle 尝试：

declare @sql nvarchar(max);
declare @id int;

create table #tmp_auditlog_subselection (
  stuff varchar(255),
  other varchar(255)
);

insert into #tmp_auditlog_subselection (stuff, other) values
  ('foo', 'bar'),
  ('baz', 'bat'),
  ('lorem', 'ipsum')
;

create table #tmp_auditlog_fields (
  id int identity(1,1),
  field varchar(255),
  details varchar(255)
);

insert into #tmp_auditlog_fields (field, details) values
  ('a', 'foo'),
  ('b', 'bar'),
  ('c', 'baz')
;

while exists(select * from #tmp_auditlog_fields where id >= @id)
    begin
        select @sql = 
            'select t.objectID, t.DocID as ' + field + 
            ' into #tmp_auditlog_' + field + 
            ' from #tmp_auditlog_subselection t where Details like ' + 
            details FROM tmp_auditlog_fields WHERE id = @i;
        exec @sql
        select @id = min(id) from #tmp_auditlog_fields where id > @id;
    end 
;

select * from #tmp_auditlog_a;

Answer 1

您在这里缺少 from 语句和 where 语句：

while @i <= @cnt
    begin
        select @sql = 
            'select t.objectID, t.DocID as ' + field + 
            ' into #tmp_auditlog_' + field + 
            ' from #tmp_auditlog_subselection t where Details like ' + details FROM #tmp_auditlog_fields WHERE id = @i
        exec sp_executesql @sql
        select @i = @i + 1
  end