Create projection without specifying KSAFE value not respecting system designed_fault_tolerance

Hi All,


Has anyone here ever encountered a problem where the creation of a projection does not respect the system designed_fault_tolerance for the default ksafety?


We are experiencing the following issue on Vertica 7.1.1-0:


1- adgear_vertica=> select designed_fault_tolerance from system;
  (1 row)



2- CREATE PROJECTION without a KSAFE clause


3- adgear_vertica=> SELECT projection_name, verified_fault_tolerance FROM projections WHERE projection_schema='production' AND anchor_table_name='test_fact_table';
      projection_name       | verified_fault_tolerance
test_fact_table_b0 |                        1
test_fact_table_b1 |                        1
test_fact_table_p  |                        0
(3 rows)


Note that test_fact_table_b0 and test_fact_table_b1 are the default superprojection from the CREATE TABLE statement.


The docs state the following, but this is not the behavior we are seeing:


"If you omit the KSAFE parameter or a KSAFE value, HP Vertica creates a single projection at the current system K-safety level. Unless you are creating a projection on a single-node database, the default KSAFE value is at least 1. "






  • For completeness, the current_default_tolerance also lists as 1:


    adgear_vertica=> SELECT designed_fault_tolerance, current_fault_tolerance FROM system;
     designed_fault_tolerance | current_fault_tolerance
                            1 |                       1
    (1 row)

  • FYI, found the following forum post which states that specifying KSAFE without a safety level accomplishes what we need.



    So the docs are definitely wrong since they say that the KSAFE parameter can also be omitted to achieve this.

  • It seems that this is caused by the following Vertica bug:


    VER-35796-Projections created without the KSAFE keyword are not at system ksafety level
    This is fixed in 7.2
    However documentation was not updated properly and it will be fixed in 7.2.1

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