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Comment:Update the change log and the SQLITE_ENABLE_STAT3 documentation.
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SHA3-256: 4c942f942caf10b34ea8ff94621200d7b4e1db4acc43cc7bb22b9b831513d438
User & Date: drh 2019-08-15 16:12:51.775
Context
2019-08-15
22:48
Update the change log with the latest enhancements. (check-in: b3e162d6ec user: drh tags: trunk)
16:12
Update the change log and the SQLITE_ENABLE_STAT3 documentation. (check-in: 4c942f942c user: drh tags: trunk)
2019-08-14
17:19
In dashboard output, group outcomes by platform. (check-in: 76662698a8 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to pages/changes.in.
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<li> Add support for the [FILTER clause on aggregate functions].
<li> The [index_info] and [index_xinfo] pragmas are enhanced to provide
     information about the on-disk representation of [WITHOUT ROWID]
     tables.
<li> Improvements to the [.recover dot-command] in the [CLI] so that
     it recovers more content from corrupt database files.
<li> Enhance the [RBU] extension to support [indexes on expressions].

}

chng {2019-07-10 (3.29.0)} {
<li> Added the [SQLITE_DBCONFIG_DQS_DML] and [SQLITE_DBCONFIG_DQS_DDL]
     actions to [sqlite3_db_config()] for activating and deactivating
     the [double-quoted string literal] misfeature.  Both default to "on"
     for legacy compatibility, but developers are encouraged to turn them








>








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<li> Add support for the [FILTER clause on aggregate functions].
<li> The [index_info] and [index_xinfo] pragmas are enhanced to provide
     information about the on-disk representation of [WITHOUT ROWID]
     tables.
<li> Improvements to the [.recover dot-command] in the [CLI] so that
     it recovers more content from corrupt database files.
<li> Enhance the [RBU] extension to support [indexes on expressions].
<li> The legacy [SQLITE_ENABLE_STAT3] compile-time option is now a no-op.
}

chng {2019-07-10 (3.29.0)} {
<li> Added the [SQLITE_DBCONFIG_DQS_DML] and [SQLITE_DBCONFIG_DQS_DDL]
     actions to [sqlite3_db_config()] for activating and deactivating
     the [double-quoted string literal] misfeature.  Both default to "on"
     for legacy compatibility, but developers are encouraged to turn them
︙︙
Changes to pages/compile.in.
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  functionality was superceded by [SQLITE_ENABLE_STAT3] as of
  SQLite [version 3.7.9] ([dateof:3.7.9]).  
  The SQLITE_ENABLE_STAT2 compile-time option
  is now a no-op.
}

COMPILE_OPTION {SQLITE_ENABLE_STAT3} {
  This option adds additional logic to the [ANALYZE] command and to
  the [query planner] that can help SQLite to chose a better query plan
  under certain situations.  The [ANALYZE] command is enhanced to collect
  histogram data from the left-most column of each index and store that data


  in the [sqlite_stat3] table.  The query planner will then use the
  histogram data to help it make better index choices.  Note, however,
  that the use of histogram data in query planner violates the
  [query planner stability guarantee] which is important to some applications.
  <p>
}

COMPILE_OPTION {SQLITE_ENABLE_STAT4} {
  This option adds additional logic to the [ANALYZE] command and to
  the [query planner] that can help SQLite to chose a better query plan
  under certain situations.  The [ANALYZE] command is enhanced to collect
  histogram data from all columns of every index and store that data
  in the [sqlite_stat4] table.  The query planner will then use the
  histogram data to help it make better index choices.  The downside of
  this compile-time option is that it violates the
  [query planner stability guarantee] making it more difficult to ensure
  consistent performance in mass-produced applications.
  <p>
  SQLITE_ENABLE_STAT4 is an enhancement of [SQLITE_ENABLE_STAT3].  STAT3
  only recorded histogram data for the left-most column of each index
  whereas the STAT4 enhancement records histogram data from all columns
  of each index.
  The [SQLITE_ENABLE_STAT3] compile-time option is a no-op and is ignored
  if the SQLITE_ENABLE_STAT4 compile-time option is used.
}

COMPILE_OPTION {SQLITE_ENABLE_TREE_EXPLAIN} {
  This compile-time option is no longer used.
}

COMPILE_OPTION {SQLITE_ENABLE_UPDATE_DELETE_LIMIT} {








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  functionality was superceded by [SQLITE_ENABLE_STAT3] as of
  SQLite [version 3.7.9] ([dateof:3.7.9]).  
  The SQLITE_ENABLE_STAT2 compile-time option
  is now a no-op.
}

COMPILE_OPTION {SQLITE_ENABLE_STAT3} {
  This option used to cause the [ANALYZE] command to collect


  index histogram data in the <b>sqlite_stat3</b> table.  But that
  functionality was superceded by [SQLITE_ENABLE_STAT4] as of
  SQLite [version 3.8.1] ([dateof:3.8.1]).  
  The SQLITE_ENABLE_STAT3 compile-time option
  continued to be supported through [version 3.29.0] ([dateof:3.29.0])
  but has now become a no-op.

  <p>
}

COMPILE_OPTION {SQLITE_ENABLE_STAT4} {
  This option adds additional logic to the [ANALYZE] command and to
  the [query planner] that can help SQLite to chose a better query plan
  under certain situations.  The [ANALYZE] command is enhanced to collect
  histogram data from all columns of every index and store that data
  in the [sqlite_stat4] table.  The query planner will then use the
  histogram data to help it make better index choices.  The downside of
  this compile-time option is that it violates the
  [query planner stability guarantee] making it more difficult to ensure
  consistent performance in mass-produced applications.
  <p>
  SQLITE_ENABLE_STAT4 is an enhancement of [SQLITE_ENABLE_STAT3].  STAT3
  only recorded histogram data for the left-most column of each index
  whereas the STAT4 enhancement records histogram data from all columns
  of each index.
  The [SQLITE_ENABLE_STAT3] compile-time option has become a no-op.

}

COMPILE_OPTION {SQLITE_ENABLE_TREE_EXPLAIN} {
  This compile-time option is no longer used.
}

COMPILE_OPTION {SQLITE_ENABLE_UPDATE_DELETE_LIMIT} {
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