如何传递数组并将其返回给存储过程？

Question

我想知道如何将数组传递给存储过程，该存储过程又将从c＃.net返回数组？

Answer 1

There are different options here depending on the scenario. I'm using SQL Server for a lot of the examples below, but much of it is broadly transferable between systems.

For a relatively small array (ideally vector) you can construct a delimited string (tab delimited, comma delimited, whatever), and pass that into your DB and parse - usually manually (DBMS often lack a "split" routine), but it is very easy to obtain a pre-written "split" implementation (for example, as a UDF in SQL Server). Typical usage:

SELECT st.*
FROM dbo.SplitUDF(@myarg) #udf
INNER JOIN SOME_TABLE st ON st.ID = #udf.Value

Xml is another option, especially for complex data; SQL Server 2005 and above has inbuilt xml parsing, but that should not be assumed in general.

Table-valued parameters are another option, but this is SQL Server 2008 only - it might well be what you are looking for, though.

Another option, especially for large data, is to pump the data into the server separately (bulk insert, SQLBulkCopy , "bcp", SSIS whatever) and process the data via SQL once it is there.

To get array/tabular data out, a standard SELECT should be your default option, although you can of course also construct xml or delimited character data. The latter can be accomplished via a quirk of SQL:

DECLARE @foo varchar(max)
SET @foo = ''
SELECT @foo = @foo + st.SomeColumn + '|' -- pipe-delimited, note trailing |
FROM SOME_TABLE st