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Comment:Document the change to PRAGMA cache_size in which a negative argument can be used to set the cache size in kibibytes.
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SHA1: 47c781b488becf2936ad6628578005a5de0ae034
User & Date: drh 2012-01-02 15:48:23
Context
2012-01-03
15:14
Updates to the psow and testing documents. check-in: d30b4960c1 user: drh tags: trunk
2012-01-02
15:48
Document the change to PRAGMA cache_size in which a negative argument can be used to set the cache size in kibibytes. check-in: 47c781b488 user: drh tags: trunk
2011-12-31
00:20
Add hyperlinks to source documetns on the requirements.html page. Add mention of the psow query parameter to the uri.html page. check-in: b69af062e6 user: drh tags: trunk
Changes
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Changes to pages/changes.in.

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    the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] I/O capability, the
    [SQLITE_POWERSAFE_OVERWRITE] compile-time option, and the
    "psow=BOOLEAN" query parameter for [URI filenames].
<li>Added the [sqlite3_db_release_memory()] interface and the
    [shrink_memory pragma].
<li>Added the [sqlite3_db_filename()] interface.
<li>Added the [sqlite3_stmt_busy()] interface.



<li>Enhanced the default memory allocator to make use of _msize() on windows,
    malloc_size() on Mac, and malloc_usable_size() on Linux.
<li>Enhanced the query planner to support index queries with range constraints
    on the rowid.
<li>Enhanced the query planner flattening logic to allow UNION ALL compounds
    to be promoted upwards to replace a simple wrapper SELECT even if the
    compounds are joins.







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    the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] I/O capability, the
    [SQLITE_POWERSAFE_OVERWRITE] compile-time option, and the
    "psow=BOOLEAN" query parameter for [URI filenames].
<li>Added the [sqlite3_db_release_memory()] interface and the
    [shrink_memory pragma].
<li>Added the [sqlite3_db_filename()] interface.
<li>Added the [sqlite3_stmt_busy()] interface.
<li>If the argument to [PRAGMA cache_size] is negative N, that means to use
    approximately -1024*N bytes of memory for the page cache regardless of
    the page size.
<li>Enhanced the default memory allocator to make use of _msize() on windows,
    malloc_size() on Mac, and malloc_usable_size() on Linux.
<li>Enhanced the query planner to support index queries with range constraints
    on the rowid.
<li>Enhanced the query planner flattening logic to allow UNION ALL compounds
    to be promoted upwards to replace a simple wrapper SELECT even if the
    compounds are joins.

Changes to pages/pragma.in.

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    <p>^When the auto_vacuum pragma is invoked with no arguments, it
    returns the current auto_vacuum mode.</p>
}

Pragma cache_size {
    <p>^(<b>PRAGMA cache_size;
       <br>PRAGMA cache_size = </b><i>Number-of-pages</i><b>;</b></p>

    <p>Query or change the suggested maximum number of database disk pages
    that SQLite will hold in memory at once per open database file.)^  Whether
    or not this suggestion is honored is at the discretion of the
    [sqlite3_pcache_methods2 | Application Defined Page Cache].

    Alternative application-defined page cache implementations
    may choose to interpret the suggested cache size in different ways
    or to ignore it all together.
    ^The default suggested cache size is 2000.</p>

    <p>^The suggested cache size is set to the absolute value of the
    <i>Number-of-pages</i> argument given to this pragma.</p>




    <p>^When you change the cache size using the cache_size pragma, the
    change only endures for the current session.  ^The cache size reverts
    to the default value when the database is closed and reopened.  Use
    the [default_cache_size]
    pragma to check the cache size permanently.</p>
}

Pragma case_sensitive_like {
    <p><b>PRAGMA case_sensitive_like = </b><i>boolean</i><b>;</b></p>
    <p>^(The default behavior of the [LIKE] operator is to ignore case
    for ASCII characters. Hence, by default <b>'a' LIKE 'A'</b> is
    true.)^  ^The case_sensitive_like pragma installs a new application-defined







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    <p>^When the auto_vacuum pragma is invoked with no arguments, it
    returns the current auto_vacuum mode.</p>
}

Pragma cache_size {
    <p>^(<b>PRAGMA cache_size;
       <br>PRAGMA cache_size = </b><i>pages</i><b>;
       <br>PRAGMA cache_size = -</b><i>kibibytes</i><b>;</b></p>
    <p>Query or change the suggested maximum number of database disk pages
    that SQLite will hold in memory at once per open database file.)^  Whether
    or not this suggestion is honored is at the discretion of the
    [sqlite3_pcache_methods2 | Application Defined Page Cache].
    The default page cache that is built into SQLite honors the request,
    however alternative application-defined page cache implementations
    may choose to interpret the suggested cache size in different ways
    or to ignore it all together.
    ^The default suggested cache size is 2000 pages.</p>


    <p>^If the argument N is positive then the suggested cache size is set 
    to N. ^If the argument N is negative, then the
    number of cache pages is adjusted to use approximately N*1024 bytes
    of memory.</p>

    <p>^When you change the cache size using the cache_size pragma, the
    change only endures for the current session.  ^The cache size reverts
    to the default value when the database is closed and reopened.</p>


}

Pragma case_sensitive_like {
    <p><b>PRAGMA case_sensitive_like = </b><i>boolean</i><b>;</b></p>
    <p>^(The default behavior of the [LIKE] operator is to ignore case
    for ASCII characters. Hence, by default <b>'a' LIKE 'A'</b> is
    true.)^  ^The case_sensitive_like pragma installs a new application-defined