Documentation Source Text

  global nChng aChng xrefChng
  set aChng($nChng) [list $date $desc $options]
  set xrefChng($date) $nChng
  incr nChng
}

chng {2017-08-31 (3.20.0)} {
<li> Update the text of error messages returned by [sqlite3_errmsg()] for some
     error codes.
<li> Added the LSM1 extension
<li> Added the [STMT virtual table] extension
<li> Added the [sqlite3_prepare_v3()] and [sqlite3_prepare16_v3()] interfaces
     with the extra "prepFlags" parameters.
<li> Provide the [SQLITE_PREPARE_PERSISTENT] flag [sqlite3_prepare_v3()] and
     use it to limit [lookaside memory] misuse by [FTS3], [FTS5], and the
     [R-Tree extension]
<li> Added the [PRAGMA secure_delete=FAST] command.  When secure_delete is
     set to FAST, old content is overwritten with zeros as long as that does
     not increase the amount of I/O.  Deleted content might still persist on
     the [free-page list] but will be purged from all b-tree pages.
<li> Enhancements to the [command-line shell]:
<ul>
<li> Add the ".cd" command.
<li> Enhance the ".schema" command to show the schema of all attached
     databases.
<li> Enhance ".tables" so that it shows the schema names for all attached
     if the name is anything other than "main".
<li> The ".import" command ignores an initial UTF-8 BOM.
<li> Added the "--newlines" option to the ".dump" command to cause U+000a and
     U+000d characters to be output literally rather than escaped using the
     [replace()] function.
</ul>
<li> Query planner enhancements:
<ul>
<li> When generating individual loops for each ORed term of an OR scan,
     move any constant WHERE expressions outside of the loop, as is 
     done for top-level loops.
<li> The query planner examines the values of bound parameters to help
     determine if a partial index is usable.
<li> When deciding between two plans with the same estimated cost, bias 
     the selection toward the one that does not use the sorter.
<li> Evaluation WHERE clause constraints involving correlated subqueries
     last, in the hope that they never have be evaluated at all.
</ul>
<li> Add [SQLITE_STMTSTATUS_REPREPARE], [SQLITE_STMTSTATUS_RUN], 
     and [SQLITE_STMTSTATUS_MEMUSED] options for the
     [sqlite3_stmt_status()] interface.
<li> Provide eponymous virtual tables for
     [PRAGMA integrity_check], [PRAGMA quick_check], and
     [PRAGMA foreign_key_check].