我有一个字符串,它可以包含由空格分隔的任意数量的单词。我通过 sqlCommand 将此字符串作为参数从 vb 发送到 sql。如何将其拆分为 sql 中的数组或将其作为数组从 vb 发送以搜索表。
sql 搜索必须返回所有那些行,其中每行包含我传递的字符串中的所有单词。
除了使用表参数外,您还可以将字符串解析为表变量。这就是伪代码的样子:
Declare a table variable with one VARCHAR column
While the string is not empty
Grab everything up to the first space and insert it into the table variable
Remove the first word from the string
获得临时表后,您可以使用 LIKE 将其与源表连接。对于源表中的每一行,连接为数组中匹配的每个单词创建一行。然后,您可以使用 GROUP/HAVING 将其限制为仅为表变量中的每个条目返回一行的结果(即与表变量中的每个字符串匹配的结果)。
例如:
DECLARE @TempTable TABLE (Word VARCHAR(100))
...
-- Put logic from the pseudocode above to populate @TempTable from your string
...
SELECT Y.PrimaryKey, MAX(Y.MaybeYouNeedThisColumnToo) from YourTable Y
INNER JOIN @TempTable temp
ON Y.ColumnToMatch LIKE '%' + temp.Word + '%'
GROUP BY Y.PrimaryKey
HAVING COUNT(*) = (SELECT COUNT(*) FROM @TempTable)
Using connection As New SqlConnection(connectionString)
Dim command As New SqlCommand("sp_GetCustomerByIDS", connection)
command.CommandType = System.Data.CommandType.StoredProcedure
'Here is how you pass in YourString seperated with comma's
command.Parameters.AddWithValue("@CustomerIDS", YourString.Replace(" ", ","))
...
End Using
逗号分隔的值字符串被传递到存储过程中(提示:请将ntext更改为 SQL2005/SQL2008+ 具有varchar(MAX)):
CREATE PROCEDURE [dbo].[sp_GetCustomerByIDS]
@CustomerIDS ntext
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @err int
declare @TempTbl as TABLE(mystrings nvarchar(32), i1 int, i2 int, i3 int)
INSERT @TempTbl exec @err = sp_SplitTextList @CustomerIDS, ','
SELECT *
FROM dbo.Customers
WHERE
dbo.Customers.ID in (select mystrings from @TempTbl)
END
我使用这个 SplitTextList 存储过程来处理逗号分隔的值,你可能想再次将 @list_text 从 text 更改为 varchar(MAX),你可以从历史中看到它相当古老:
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */
-- uspSplitTextList
--
-- Description:
-- splits a separated list of text items and returns the text items
--
-- Arguments:
-- @list_text - list of text items
-- @Delimiter - delimiter
--
-- Notes:
-- 02/22/2006 - WSR : use DATALENGTH instead of LEN throughout because LEN doesn't count trailing blanks
--
-- History:
-- 02/22/2006 - WSR : revised algorithm to account for items crossing 8000 character boundary
--
CREATE PROCEDURE [dbo].[sp_SplitTextList]
@list_text text,
@Delimiter varchar(3)
AS
SET NOCOUNT ON
DECLARE @InputLen integer -- input text length
DECLARE @TextPos integer -- current position within input text
DECLARE @Chunk varchar(8000) -- chunk within input text
DECLARE @ChunkPos integer -- current position within chunk
DECLARE @DelimPos integer -- position of delimiter
DECLARE @ChunkLen integer -- chunk length
DECLARE @DelimLen integer -- delimiter length
DECLARE @ItemBegPos integer -- item starting position in text
DECLARE @ItemOrder integer -- item order in list
DECLARE @DelimChar varchar(1) -- first character of delimiter (simple delimiter)
-- create table to hold list items
-- actually their positions because we may want to scrub this list eliminating bad entries before substring is applied
CREATE TABLE #list_items ( item_order integer, item_begpos integer, item_endpos integer )
-- process list
IF @list_text IS NOT NULL
BEGIN
-- initialize
SET @InputLen = DATALENGTH(@list_text)
SET @TextPos = 1
SET @DelimChar = SUBSTRING(@Delimiter, 1, 1)
SET @DelimLen = DATALENGTH(@Delimiter)
SET @ItemBegPos = 1
SET @ItemOrder = 1
SET @ChunkLen = 1
-- cycle through input processing chunks
WHILE @TextPos <= @InputLen AND @ChunkLen <> 0
BEGIN
-- get current chunk
SET @Chunk = SUBSTRING(@list_text, @TextPos, 8000)
-- setup initial variable values
SET @ChunkPos = 1
SET @ChunkLen = DATALENGTH(@Chunk)
SET @DelimPos = CHARINDEX(@DelimChar, @Chunk, @ChunkPos)
-- loop over the chunk, until the last delimiter
WHILE @ChunkPos <= @ChunkLen AND @DelimPos <> 0
BEGIN
-- see if this is a full delimiter
IF SUBSTRING(@list_text, (@TextPos + @DelimPos - 1), @DelimLen) = @Delimiter
BEGIN
-- insert position
INSERT INTO #list_items (item_order, item_begpos, item_endpos)
VALUES (@ItemOrder, @ItemBegPos, (@TextPos + @DelimPos - 1) - 1)
-- adjust positions
SET @ItemOrder = @ItemOrder + 1
SET @ItemBegPos = (@TextPos + @DelimPos - 1) + @DelimLen
SET @ChunkPos = @DelimPos + @DelimLen
END
ELSE
BEGIN
-- adjust positions
SET @ChunkPos = @DelimPos + 1
END
-- find next delimiter
SET @DelimPos = CHARINDEX(@DelimChar, @Chunk, @ChunkPos)
END
-- adjust positions
SET @TextPos = @TextPos + @ChunkLen
END
-- handle last item
IF @ItemBegPos <= @InputLen
BEGIN
-- insert position
INSERT INTO #list_items (item_order, item_begpos, item_endpos)
VALUES (@ItemOrder, @ItemBegPos, @InputLen)
END
-- delete the bad items
DELETE FROM #list_items
WHERE item_endpos < item_begpos
-- return list items
SELECT SUBSTRING(@list_text, item_begpos, (item_endpos - item_begpos + 1)) AS item_text, item_order, item_begpos, item_endpos
FROM #list_items
ORDER BY item_order
END
DROP TABLE #list_items
RETURN