Return rows where first character is non-alpha

问题

I'm trying to retrieve all columns that start with any non alpha characters in SQlite but can't seem to get it working. I've currently got this code, but it returns every row:

SELECT * FROM TestTable WHERE TestNames NOT LIKE '[A-z]%'

Is there a way to retrieve all rows where the first character of TestNames are not part of the alphabet?

回答1:

Are you going first character only?

select * from TestTable WHERE substr(TestNames,1) NOT LIKE '%[^a-zA-Z]%'

The substr function (can also be called as left() in some SQL languages) will help isolate the first char in the string for you.

edit: Maybe substr(TestNames,1,1) in sqllite, I don't have a ready instance to test the syntax there on.

Added:

select * from TestTable WHERE Upper(substr(TestNames,1,1)) NOT in ('A','B','C','D','E',....)

Doesn't seem optimal, but functionally will work. Unsure what char commands there are to do a range of letters in SQLlite.

I used 'upper' to make it so you don't need to do lower case letters in the not in statement...kinda hope SQLlite knows what that is.

回答2:

try

SELECT * FROM TestTable WHERE TestNames NOT LIKE '[^a-zA-Z]%'

回答3:

SELECT * FROM NC_CRIT_ATTACH WHERE substring(FILENAME,1,1) NOT LIKE '[A-z]%'; SHOULD be a little faster as it is A) First getting all of the data from the first column only, then scanning it. B) Still a full-table scan unless you index this column.

来源：https://stackoverflow.com/questions/11196538/return-rows-where-first-character-is-non-alpha