To customize SQL name mappings

If you need to add or modify a function or special register mapping, you can use any text editor to make changes to DialectMappings.hcomap, located in the $COBDIR/etc/hcoss directory.

Function Customization Example

create function atanh (@in float) returns float
begin
	return log((1 + @in) / (1 - @in)) / 2
end
go

declare @x float = 0.75
select dbo.atanh(@x)

Insert the following right before the end tag </NameMappingDataSet> in DialectMappings.hcomap and save:

<DB2NameMapping>
    <DB2Name>atanh</DB2Name>
    <SQLServerName>dbo.atanh</SQLServerName>
    <IsFunction>true</IsFunction>
    <IsSpecialRegister>false</IsSpecialRegister>
  </DB2NameMapping>