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From Gunnar Tapper <tapper.gun...@gmail.com>
Subject Re: Documenting CQDs
Date Mon, 29 Feb 2016 05:21:22 GMT
Hi,

This leads me witht the following. WMS_* can be excluded. Any other one?

 XDDkwd__(AUTO_QUERY_RETRY_WARNINGS,            "OFF"),
 XDDkwd__(BLOCK_TO_PREVENT_HALLOWEEN,           "ON"),
 XDDui___(CACHE_HISTOGRAMS_REFRESH_INTERVAL,  "3600"),
 XDDansi_(CATALOG, TRAFODION_SYSCAT_LIT),
  XDDkwd__(COMPRESSION_TYPE, "NONE"),
 XDDui1__(DEFAULT_DEGREE_OF_PARALLELISM,    "2"),
  XDDui1__(DEF_MAX_HISTORY_ROWS, "1024"),
 XDDkwd__(DISPLAY_DIVISION_BY_COLUMNS,          "OFF"),
  XDDui___(EXE_MEMORY_LIMIT_PER_CPU, "0"),
 XDDui___(EXPLAIN_DESCRIPTION_COLUMN_SIZE,    "-1"),
  // HASH_JOINS ON means do HASH_JOINS
 XDDkwd__(HASH_JOINS, "ON"),
 XDDkwd__(HIST_AUTO_GENERATION_OF_SAMPLE,       "OFF"),
  // This CQD is used to control the number of missing stats warnings
  // that should be generated.
  // 0 ? Display no warnings.
  // 1 ? Display only missing single column stats warnings. These include
6008 and 6011
  // 2 ? Display all single column missing stats warnings and
  //     multi-column missing stats warnings for Scans only.
  // 3 ? Display all missing single column stats warnings and missing
  //     multi-column stats warnings for Scans and Join operators only..
  // 4 ? Display all missing single column stats and missing multi-column
  //     stats warnings for all operators including Scans, Joins and
GroupBys.
  // The CQD also does not have an impact on the auto update stats
behavior. The stats will
  // still be automatically generated even if the warnings have been
suppressed.
  // USTAT_AUTO_MISSING_STATS_LEVEL.
  // Default behavior is to generate all warnings
  XDDui___(HIST_MISSING_STATS_WARNING_LEVEL, "4"),

  // This specifies the time interval after which the fake statistics
  // should be refreshed. This was done primarirly for users
  // which did not want to update statistics on temporary tables.
  // If this statistics is cached, then this results in bad plans
  // These users can have this default set to 0, in which case histograms
  // with fake statistics will never be cached.  Note that when ustat
  // automation is on, this value divided by 360 is used.

 XDDui___(HIST_NO_STATS_REFRESH_INTERVAL,       "3600"),
 XDDkwd__(HIST_PREFETCH,                        "ON"),
 XDDkwd__(HIST_REMOVE_TRAILING_BLANKS,          "ON"), // should remove
after verifying code is solid
 XDDflt1_(HIST_ROWCOUNT_REQUIRING_STATS,        "500"),
 XDDkwd__(HIST_USE_SAMPLE_FOR_CARDINALITY_ESTIMATION ,      "ON"),
 XDDkwd__(INSERT_VSBB, "SYSTEM"),
 XDDkwd__(ISOLATION_LEVEL, "READ_COMMITTED"),
XDDkwd__(ISOLATION_LEVEL_FOR_UPDATES, "NONE"),
  // Force the join order given by the user
 XDDkwd__(JOIN_ORDER_BY_USER, "OFF"),
 XDDkwd__(LAST0_MODE, "OFF"),
  // For old MCSB (that is, we guess MC skews from SC skews),
  //  apply the MC skew buster when
  //   SFa,b... * countOfPipeline > MC_SKEW_SENSITIVITY_THRESHOLD
  //   SFa,b ... is the skew factor for multi column a,b,...
  //
  XDDflt__(MC_SKEW_SENSITIVITY_THRESHOLD,        "0.1"),
  // controls the max. number of seek positions under which MDAM will be
  // allowed. Set it to 0 turns off the feature.
  XDDui___(MDAM_NO_STATS_POSITIONS_THRESHOLD,       "10"),

  // MDAM_SCAN_METHOD ON means MDAM is enabled,
  // OFF means MDAM is disabled. MDAM is enabled by default
  // externalized 06/21/01 RV
 // mdam off on open source at this point
  XDDkwd__(MDAM_SCAN_METHOD, "ON"),
  // controls the max. number of probes at which MDAM under NJ plan will be
  // generated. Set it to 0 turns off the feature.
  XDDui___(MDAM_UNDER_NJ_PROBES_THRESHOLD,       "0"),

  // MERGE_JOINS ON means do MERGE_JOINS
 XDDkwd__(MERGE_JOINS, "ON"),
  // Allow for the setting of the row count in a long running operation
 XDDui1__(MULTI_COMMIT_SIZE, "10000"),


//--------------------------------------------------------------------------
  //++ MV
 XDDkwd__(MVGROUP_AUTOMATIC_CREATION,           "ON"),
 XDDkwd__(MVQR_REWRITE_ENABLED_OPTION,    "OFF"),  // @ZX -- change to ON
later
 XDDui0_5(MVQR_REWRITE_LEVEL,             "0"),
 XDDkwd__(MVQR_REWRITE_SINGLE_TABLE_QUERIES, "ON"),

 XDDMVA__(MV_AGE, ""),
 XDDkwd__(MV_ALLOW_SELECT_SYSTEM_ADDED_COLUMNS, "OFF"),
  // NESTED_JOINS ON means do NESTED_JOINS
 XDDkwd__(NESTED_JOINS, "ON"),
  XDDui30_32000(NOT_ATOMIC_FAILURE_LIMIT,       "32000"),
 XDDui___(OPI_ERROR73_RETRIES,                  "10"),
 XDDkwd__(OPTIMIZATION_LEVEL, "3"),
  // If PARALLEL_NUM_ESPS is "SYSTEM",
  // optimizer will compute the number of ESPs.
 XDDui1__(PARALLEL_NUM_ESPS, "SYSTEM"),
  // Partition OVerlay Support (POS) options
  XDDpos__(POS_ABSOLUTE_MAX_TABLE_SIZE,                 ""),
 XDDrlis_(PUBLISHING_ROLES, ""),
 // query_cache max should be 200 MB. Set it 0 to turn off query cache
 //XDD0_200000(QUERY_CACHE,                  "0"),
 XDD0_200000(QUERY_CACHE,                  "16384"),
  // multiplicative factor used to inflate cost of risky operators.
  // = 1.0 means do not demand an insurance premium from risky operators.
  // = 1.2 means demand a 20% insurance premium that cost of risky operators
  // must overcome before they will be chosen over less-risky operators.
 XDDflt0_(RISK_PREMIUM_NJ,     "1.0"),
 XDDflt0_(RISK_PREMIUM_SERIAL, "1.0"),
 XDDui___(RISK_PREMIUM_SERIAL_SCALEBACK_MAXCARD_THRESHOLD, "10000"),

  // external master CQD that sets following internal CQDs
  //                              robust_query_optimization
  //                              MINIMUM  SYSTEM  HIGH MAXIMUM
  // risk_premium_NJ                 1.0   system  2.5  5.0
  // risk_premium_SERIAL             1.0   system  1.5  2.0
  // partitioning_scheme_sharing     0     system  2    2
  // robust_hj_to_nj_fudge_factor    0.0   system  3.0  1.0
  // robust_sortgroupby              0     system  2    2
  // risk_premium_MJ                 1.0   system  1.5  2.0
  // see optimizer/ControlDB.cpp ControlDB::doRobustQueryOptimizationCQDs
  // for the actual cqds that set these values
 XDDkwd__(ROBUST_QUERY_OPTIMIZATION,            "SYSTEM"),

 XDDkwd__(SAVE_DROPPED_TABLE_DDL,               "OFF"),
 XDDansi_(SCHEMA,                               "SEABASE"),
 XDDkwd__(SKEW_EXPLAIN,                         "ON"),
 XDDflt__(SKEW_ROWCOUNT_THRESHOLD,              "1000000"), // Column row
count
                                                           // threshold
below
                                                           // which skew
                                                           // buster is
disabled.
 XDDflt__(SKEW_SENSITIVITY_THRESHOLD,           "0.1"),
  // Timeout for a streaming cursor to return to the fetch(), even if no
  // rows to return.  The cursor is NOT closed, it just gives control to
  // the user again.
  // "0" means no timeout, just check instead.
  // "negative" means never timeout.
  // "positive" means the number of centiseconds to wait before timing out.
 XDDint__(STREAM_TIMEOUT, "-1"),

 XDDkwd__(SUBQUERY_UNNESTING, "ON"),
 XDDkwd__(TABLELOCK, "SYSTEM"),

 XDDintN2(TIMEOUT, "6000"),
  // DTM Transaction Type: MVCC, SSCC
  XDDkwd__(TRAF_TRANS_TYPE,                            "MVCC"),
  XDDui___(UDR_DEBUG_FLAGS,                      "0"), // see
sqludr/sqludr.h for values
 XDDui___(UDR_JVM_DEBUG_PORT,                   "0"),
 XDDui___(UDR_JVM_DEBUG_TIMEOUT,                "0"),
 XDDkwd__(UPD_ORDERED, "ON"),
 XDDflt0_(USTAT_AUTO_CV_SAMPLE_SLOPE,           "0.5"),  // CV multiplier
for sampling %.
 XDDui___(USTAT_AUTO_PRIORITY,                  "150"),  // Priority of
ustats under USAS.
 XDDui___(USTAT_MAX_READ_AGE_IN_MIN,            "5760"),
 XDDui1__(USTAT_MIN_ROWCOUNT_FOR_LOW_SAMPLE,    "1000000"),
 XDDui1__(USTAT_MIN_ROWCOUNT_FOR_SAMPLE,        "10000"),
 XDDui1__(USTAT_NECESSARY_SAMPLE_MAX,           "5000000"), // Maximum
sample size with NECESSARY
 XDDpct__(USTAT_OBSOLETE_PERCENT_ROWCOUNT,      "15"),
 XDDui1__(USTAT_YOULL_LIKELY_BE_SORRY,          "100000000"),  // guard
against unintentional long-running UPDATE STATS
 XDDkwd__(WMS_CHILD_QUERY_MONITORING,                       "OFF"),
 XDDkwd__(WMS_QUERY_MONITORING,                       "OFF"),

Thanks,

Gunnar

On Sun, Feb 28, 2016 at 6:07 AM, Qifan Chen <qifan.chen@esgyn.com> wrote:

> Hi,
>
> We probably should not expose SDDxxxx ones since they are internal. XDDxxx
> CQDs are external ones.
>
> --Qifan
>
> On Sun, Feb 28, 2016 at 1:14 AM, Gunnar Tapper <tapper.gunnar@gmail.com>
> wrote:
>
> > Hi,
> >
> > I'm looking at core/sql/sqlcomp/nadefaults.cpp.
> >
> > Should SDDxxxx CQDs be documented or just XDDxxxx CQDs?
> >
> >
> > --
> > Thanks,
> >
> > Gunnar
> > *If you think you can you can, if you think you can't you're right.*
> >
>
>
>
> --
> Regards, --Qifan
>



-- 
Thanks,

Gunnar
*If you think you can you can, if you think you can't you're right.*

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