Documentation Source Text

    set xrefChng($vers) $nChng
  }
  incr nChng
}

chng {2020-08-22 (3.33.0)} {
<li> Support for [UPDATE FROM] following the PostgreSQL syntax.
<li> Extended the [PRAGMA integrity_check] statement so that it can optionally be
     limited to verifying just a single table and its indexes, rather than the
     entire database file.
<li> Added the [decimal extension] for doing arbitrary-precision decimal arithmetic.
<li> Enhancments to the [ieee754 extension] for working with IEEE 754 binary64 numbers.
<li> [CLI] enhancements:
    <ol type="a">
    <li> Added four new [.mode|output modes]: "box", "json", "markdown",
         and "table".
    <li> The "column" output mode automatically expands columns to

    from the returned option names.  See also the
    [sqlite3_compileoption_get()] C/C++ interface and the
    [sqlite_compileoption_get()] SQL functions.</p>
}

Pragma integrity_check {
    <p><b>PRAGMA DB.integrity_check;
      <br>PRAGMA DB.integrity_check(</b><i>N</i><b>)
      <br>PRAGMA DB.integrity_check(</b><i>TABLENAME</i><b>)</b></p>
    <p>^This pragma does a low-level formatting and consistency check
    of the database.  ^The integrity_check pragma look for:
    <ul>
    <li> Table or index entries that are out of sequence
    <li> Misformatted records
    <li> Missing pages
    <li> Missing or surplus index entries
    <li> UNIQUE, CHECK, and NOT NULL constraint errors
    <li> Integrity of the freelist
    <li> Sections of the database that are used more than once, or not at all
    </ul>
    <p>^If the integrity_check pragma finds problems, strings are returned
    (as multiple rows with a single column per row) which describe
    the problems.  ^Pragma integrity_check will return at most <i>N</i>
    errors before the analysis quits, with N defaulting
    to 100.  ^If pragma integrity_check finds no errors, a
    single row with the value 'ok' is returned.</p>

    <p>^The usual case is that the entire database file is checked.  However,
    if the argument is <i>TABLENAME</i>, then checking is only performed for the
    the table named and its associated indexes.
    This is called a "partial integrity check".  Because only a subset of the
    database is checked, errors such as unused sections of the file or duplication
    use of the same section of the file by two or more tables cannot be detected.
    The freelist is only verified on a
    partial integrity check if <i>TABLENAME</i> is [sqlite_schema] or one of its
    aliases.  Support for partial integrity checks was added with
    version 3.33.0 ([dateof:3.33.0]).

    <p>PRAGMA integrity_check does not find
    [foreign key constraint|FOREIGN KEY] errors.  
    Use the [PRAGMA foreign_key_check] command for to find errors in
    FOREIGN KEY constraints.</p>

    <p>See also the [PRAGMA quick_check] command which does most of the
    checking of PRAGMA integrity_check but runs much faster.</p>
}

Pragma quick_check {
    <p><b>PRAGMA DB.quick_check;
      <br>PRAGMA DB.quick_check(</b><i>N</i><b>)</b>
      <br>PRAGMA DB.quick_check(</b><i>TABLENAME</i><b>)</b></p>
    <p>^The pragma is like [integrity_check] except that it does not verify
    UNIQUE constraints and does not verify
    that index content matches table content.  By skipping UNIQUE
    and index consistency checks, quick_check is able to run faster.
    PRAGMA quick_check runs in O(N) time whereas [PRAGMA integrity_check]
    requires O(NlogN) time where N is the total number of rows in the 
    database. ^Otherwise the two pragmas are the same.
    </p>
}

DebugPragma parser_trace {
    <p><b>PRAGMA parser_trace = </b><i>boolean</i><b>; </b></p>

    <p>If SQLite has been compiled with the [SQLITE_DEBUG] compile-time