替换包含表中列的任何结果的字符串的一部分

Question

I'm attempting to replace part of a string in a table with specific text if the string contains the exact string from a column in a table.

I've created a list of just the strings i want to modifying into a variable table, then connecting to the target table with a CROSS JOIN , however the amount of data within the two tables means a cross join could end up coming to hundreds of millions of rows, and the vast majority of the strings i want to swap the data out with will likely not contain any of the data from the second table.

There also isn't any method of identifying which records in table 1 will get modified, as there are no identifiers within the string i want to modify. what I have already is below:

DECLARE @Table2 TABLE (T2.Column1 Varchar(100), T2.Column2 INT)


INSERT INTO @Table2
Select
    T3.Column2 + ', ' + T3.Column3,
    T3.Column1
FROM Table3 T3
    WHERE T3.Column1 IN (1,2,3,4)

UPDATE Table1 SET Column1 = REPLACE(T1.Column1, T2.Column1, 'String')
        FROM Table1 T1
        CROSS JOIN @Table2 T2

I've also attempted the same thing using a CROSS APPLY instead of a CROSS JOIN , but the performance remains the same.

This does work, however the performance is poor due to having to join every row on both tables. Is there any method where i can achieve the same result but without joining every row to compare?

EDIT:

sample data:

CREATE TABLE Table1 ([Column1] varchar(4000), [Column2] INT)
CREATE TABLE Table3 ([Column1] INT, [Column2] Varchar(50), [Column3] Varchar(50))

INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example Data To Replace 1: text, example', 1)
INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example Data To Replace 2 example text', 2)
INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example Data To Replace 3', 3)
INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example Data To, Replace 4 extra text', 4)
INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example Data To, Replace 5', 5)
INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example Data To Replace 6', 6)
INSERT [dbo].[Table1] ([Column1], [Column2]) VALUES ('Example, Data To Replace 7', 7)

INSERT [dbo].[Table3] ([Column1], [Column2], [Column3]) VALUES (1, 'text', 'example')
INSERT [dbo].[Table3] ([Column1], [Column2], [Column3]) VALUES (2, 'To', 'Replace')
INSERT [dbo].[Table3] ([Column1], [Column2], [Column3]) VALUES (3, 'Example', 'Data')

I would have expected it to return the following, but its only actually corrected the first line in table1:

Column1                                     Column2
Example Data To Replace 1: String           1
Example Data To Replace 2 example text      2
Example Data To Replace 3                   3
Example Data String 4 extra text            4
Example Data String 5                       5
Example Data To Replace 6                   6
String To Replace 7                         7

Answer 1

I don't understand why you use cross join when you can use inner join instead:

UPDATE T1 
SET T1.Column1 = REPLACE(T1.Column1, T2.Column1, 'String')
FROM Table1 As T1 
JOIN Table2 As T2 ON T1.Column1 LIKE '%'+ T2.Column1 +'%'

This will only update the records where there is actually something to update, and should have much better performance then a cross join. If it still suffers a performance issue, you might want to use full text search instead of like.

You can see a live demo on rextester.