Postgres Stored Procedure to Clean Up Phone Numbers

We need stored procedures and an example of how to update an entire table in SQL to do the following: 1) strip out all non-numeric characters from each phone number (i.e., remove all ( and ) and . and - characters plus anything else in there) 2) if the resulting number starts with a 1, remove the 1 A suggested SQL Server based procedure is as follows: ALTER FUNCTION [dbo].[RemoveChars](@Str varchar(1000)) RETURNS VARCHAR(1000) BEGIN declare @NewStr varchar(1000), @i int set @i = 1 set @NewStr = '' while @i <= len(@str) begin --grab digits or (| in regex) decimal if substring(@str,@i,1) like '%[0-9]%' begin set @NewStr = @NewStr + substring(@str,@i,1) end else begin set @NewStr = @NewStr end set @i = @i + 1 end RETURN Rtrim(Ltrim(@NewStr)) END The second one removes the leading 1 if the phone number begins with a 1 and then checks if the phone number is longer than 10 characters, in which case it trims it to 10: ALTER FUNCTION [dbo].[Remove1AndCut](@Str varchar(1000)) RETURNS VARCHAR(1000) BEGIN declare @NewStr varchar(1000) --,@i int --set @i = 1 set @NewStr = '' --while @i <= len(@str) --begin --grab digits or (| in regex) decimal if substring(@str,1,1) = '1' begin set @NewStr = @NewStr + substring(@str,2,len(@str)) end if len(@str)>10 begin set @NewStr = substring(@str,1,10) end else begin set @NewStr = @NewStr end --set @i = @i + 1 --end RETURN Rtrim(Ltrim(@NewStr)) END This should work on latest PostgreSQL