Stripping out dates, of several formats, from strings - sql-server

Question

I have a column of strings, called "MyStrings" like the following:
...
Foo bar Jul15 blah blah.xlsx
Choo bar Jul-15 blah far.xlsx
Star bar 10-Jul-15 blah far.xlsx
Car Star bar 10.Jul.2015 blah far.xlsx
...
...
I'd like to do string manipulation so all dates, whatever format, are not included in the results.
So the following query:
SELECT results = <manipulated "MyStrings">
FROM aTable
Should have these results:
...
Foo bar blah blah.xlsx
Choo bar blah far.xlsx
Star bar blah far.xlsx
Car Star bar blah far.xlsx
...
...
Is there a quick way of doing this or do I need to consider each format individually?

Answer 1

You need a Split function
If you split first by <space> is easy create regular expresion for
monDD
mon-DD
DD-mon-YY
DD-mon-YYYY
SQL Fiddle Demo
WITH splitCTE AS (
SELECT s.[id], f.Number, f.Item
FROM dbo.SourceData AS s
CROSS APPLY dbo.SplitStrings(s.[test], ' ') as f
)
SELECT *,
CASE
WHEN item Like 'Jul[0-9][0-9]' THEN 'mmmdd'
WHEN item Like 'Jul-[0-9][0-9]' THEN 'mmm-dd'
WHEN item Like '[0-9][0-9]-Jul-[0-9][0-9]' THEN 'dd-mmm-yy'
WHEN item Like '[0-9][0-9].Jul.[0-9][0-9][0-9][0-9]' THEN 'dd.mmm.yyyy'
ELSE ''
END matchType
FROM splitCTE
OUTPUT
Need a join with list of 3 char months to replace the wired Jul.
Easy expand to also include a version with full month name.
Will match Jul77 as mmmdd but is a start.
You can calculate a IsValidDate column in another step
For some of the format you can use CONVERT to check for a valid date
For other like Jul77 you can separate first 3 char with last 2 and try to get a date.
.
| id | Number | Item | matchType |
|----|--------|-------------|-------------|
| 1 | 1 | Foo | |
| 1 | 2 | bar | |
| 1 | 3 | Jul15 | mmmdd |
| 1 | 4 | blah | |
| 1 | 5 | blah.xlsx | |
| 2 | 1 | Choo | |
| 2 | 2 | bar | |
| 2 | 3 | Jul-15 | mmm-dd |
| 2 | 4 | blah | |
| 2 | 5 | far.xlsx | |
| 3 | 1 | Star | |
| 3 | 2 | bar | |
| 3 | 3 | 10-Jul-15 | dd-mmm-yy |
| 3 | 4 | blah | |
| 3 | 5 | far.xlsx | |
| 4 | 1 | Car | |
| 4 | 2 | Star | |
| 4 | 3 | bar | |
| 4 | 4 | 10.Jul.2015 | dd.mmm.yyyy |
| 4 | 5 | blah | |
| 4 | 6 | far.xlsx | |
Then use your favorite XML PATH to join back without the matching elements