View -> DBA -> Database configuration -> Initialization Parameters -> right click "Open" -> editor with "Parameter" and "Value" (inter alia) columns appears
Changing value for parameter "optimizer_features_enable" isn't working:
Changing value from 126.96.36.199 to 9.2.0 -> commiting changes -> ORA-02017 error appears ("integer value required")
In "Messages - Log" window appears the following statement: ALTER SYSTEM SET optimizer_features_enable=9.2.0 COMMENT='' SCOPE=MEMORY
I think rather it should be: ALTER SYSTEM SET optimizer_features_enable='9.2.0' COMMENT='' SCOPE=MEMORY
One workaround for this case is, when editing the data in the grid cell, to enclose the Oracle version in single quotes. After committing to apply the update (which works), the grid refresh strips away the single quotes, leaving the desired value displayed in the cell.
So this is, as you say, a small bug. Note that not all parameters of type String require single quotes, e. g., cursor_sharing=exact. Probably any String beginning with a numeric digit should be enclosed in quotes automatically.
I logged the following bug: Bug 16733790 - UPDATING INITIALIZATION PARAMETER OF TYPE STRING FAILS IF BEGINS WITH A NUMERIC
Thanks for reporting this,
SQL Developer Team