Documentation Source Text

set nChng 0
proc chng {date desc {options {}}} {
  global nChng aChng
  set aChng($nChng) [list $date $desc $options]
  incr nChng
}

chng {2015-00-00 (3.8.11)} {
<li>Added the [sqlite3_value_dup()] and [sqlite3_value_free()] interfaces.
<li>The [IS operator] is now able to drive indexes.
<p><b>Bug fixes:</b>
<li>Fix to CREATE TABLE AS so that columns of type TEXT never end up holding an INT
    value.  Ticket
    [https://www.sqlite.org/src/info/f2ad7de056ab1dc9200|f2ad7de056ab1dc9200]
}

chng {2015-05-20 (3.8.10.2)} {
<li>Fix an index corruption issue introduced by [version 3.8.7].  An index
    with a TEXT key can be corrupted by an [INSERT] into the corresponding 
    table if the table has two nested triggers that convert the key value to INTEGER
    and back to TEXT again.
    Ticket [https://www.sqlite.org/src/info/34cd55d68e0e6e7c9a0711aab81a2ee3c354b4c0|34cd55d68e0]

<li>SQLITE_SOURCE_ID: "2015-05-20 18:17:19 2ef4f3a5b1d1d0c4338f8243d40a2452cc1f7fe4"
<li>SHA1 for sqlite3.c: 638abb77965332c956dbbd2c8e4248e84da4eb63
} {patchagainst 1 patchagainst 2}

chng {2015-05-09 (3.8.10.1)} {
<li>Make [sqlite3_compileoption_used()] responsive to the [SQLITE_ENABLE_DBSTAT_VTAB]
    compile-time option.
<li>Fix a harmless warning in the [command-line shell] on some versions of MSVC.
<li>Fix minor issues with the [dbstat virtual table].

<li>SQLITE_SOURCE_ID: "2015-05-09 12:14:55 05b4b1f2a937c06c90db70c09890038f6c98ec40"

</td>
<td width="20"></td><td bgcolor="#044a64" width="1"></td><td width="20"></td>
<td valign="top">
<h3>Current Status</h3>

<p><ul>
<li><a href="releaselog/3_8_11.html">Version 3.8.11</a>
of SQLite is recommended for all new development.
</li>
</ul></p>

<h3>Common Links</h3>

<p><ul>

  hd_puts "<h3>$date - $title</h3>"
  regsub -all "\n( *\n)+" $text "</p>\n\n<p>" txt
  regsub -all {[Tt]icket #(\d+)} $txt \
      {<a href="http://www.sqlite.org/cvstrac/tktview?tn=\1">\0</a>} txt
  hd_resolve "<blockquote>$txt</blockquote>"
  hd_puts "<hr width=\"50%\">"
}

newsitem {2015-05-20} {Release 3.8.10.2} {
<p>Yikes!  Index corruption after a sequence of valid SQL statements!
<p>It has been many years since anything like 
   [https://www.sqlite.org/src/info/34cd55d6|this bug] has snuck into
   an official SQLite release.  But for the pasts seven months
   ([version 3.8.7] through [version 3.8.10.1])
   if you do an INSERT into a carefully
   crafted schema in which there are two nested triggers that convert
   an index key value from TEXT to INTEGER and then back
   to TEXT again, the INTEGER value might get inserted as the index
   key instead of the correct TEXT, resulting in index corruption.
   This patch release adds a single line of code to fix the problem.
<p>If you do actually encounter this problem, running [REINDEX] on the
   damaged indexes will clear it.
}

newsitem {2015-05-09} {Release 3.8.10.1} {
<p>The 3.8.10 release did not add the new [SQLITE_ENABLE_DBSTAT_VTAB]
   compile-time option to the [sqlite3_compileoption_used()] interface.
   This patch release fixes that omission.  And while we are at it,
   the associated [dbstat virtual table] was enhanced slightly and a
   harmless compiler warning was fixed.

"-g -fprofile-arcs -ftest-coverage" and then the test program is run.
Then "gcov -b" is run to generate a coverage report.
The coverage report is verbose and inconvenient to read, 
so the gcov-generated report is processed using
some simple scripts to put it into a more human-friendly format.
This entire process is automated using scripts, of course.

<p>Note that running SQLite with gcov is not a test of SQLite &mdash;
it is a test of the test suite.  The gcov run does not test SQLite because
the -fprofile-args and -ftest-coverage options cause the compiler to 
generate different code.  
The gcov run merely verifies that the test suite provides 100% branch test
coverage.  The gcov run is a test of the test - a meta-test.

<p>After gcov has been run to verify 100% branch test coverage,
then the test program is recompiled using delivery compiler options
(without the special -fprofile-arcs and -ftest-coverage options)
and the test program is rerun.
This second run is the actual test of SQLite.

<p>It is important to verify that the gcov test run 
and the second real test run both give the same output.  Any
differences in output indicate either the use of undefined or
indeterminate behavior in the SQLite code (and hence a bug), 
or a bug in the compiler.
Note that SQLite has, over the previous decade, encountered bugs
in each of GCC, Clang, and MSVC.  Compiler bugs, while rare, do happen,
which is why it is so important to test the code in an as-delivered
configuration.

<tcl>hd_fragment thoughts1</tcl>
<h3>7.6 Experience with full test coverage</h3>

<p>The developers of SQLite have found that full coverage testing is an
extremely effective method for locating and preventing bugs.
Because every single branch
instruction in SQLite core code is covered by test cases, the developers
can be confident that changes made in one part of the code
do not have unintended consequences in other parts of the code.
The many new features and performance improvements that have been
added to SQLite in recent years would not have been possible without
the availability full-coverage testing.</p>

<p>Maintaining 100% MC/DC is laborious and time-consuming.
The level of effort needed to maintain full-coverage testing
is probably not cost effective for a typical application.
However, we think that full-coverage testing is justified for a
[most widely deployed|very widely deployed] infrastructure library
like SQLite, and especially for a database library which by its very
nature "remembers" past mistakes.


<tcl>hd_fragment dynamicanalysis</tcl>
<h2>8.0 Dynamic Analysis</h2>

<p>Dynamic analysis refers to internal and external checks on the
SQLite code which are performed while the code is live and running.
Dynamic analysis has proven to be a great help in maintaining the