Waiting for 9.2 – More rewrite-less ALTER TABLE ALTER TYPEs

Three patches for you today, all committed by Robert Hass:

  • On 7th of February, patch:
    Add a transform function for numeric typmod coercisions.
     
    This enables ALTER TABLE to skip table and index rebuilds when a column
    is changed to an unconstrained numeric, or when the scale is unchanged
    and the precision does not decrease.
     
    Noah Misch, with a few stylistic changes and a fix for an OID
    collision by me.
  • also on 7th, patch:
    Add a transform function for varbit typmod coercisions.
     
    This enables ALTER TABLE to skip table and index rebuilds when the
    new type is unconstraint varbit, or when the allowable number of bits
    is not decreasing.
     
    Noah Misch, with review and a fix for an OID collision by me.
  • and a day later final patch:
    Add transform functions for various temporal typmod coercisions.
     
    This enables ALTER TABLE to skip table and index rebuilds in some cases.
     
    Noah Misch, with trivial changes by me.

Continue reading Waiting for 9.2 – More rewrite-less ALTER TABLE ALTER TYPEs

Waiting for 9.1 – adding values to enums

Finally, on 25th of October, Tom Lane committed patch which does:

Allow new values to be added to an existing enum type.
 
After much expenditure of effort, we've got this to the point where the
performance penalty is pretty minimal in typical cases.
 
Andrew Dunstan, reviewed by Brendan Jurd, Dean Rasheed, and Tom Lane

Continue reading Waiting for 9.1 – adding values to enums