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Comment:Clarify the documentation on PRAGMA cache_size to explain that the cache size will go up or down in proportion to a change in page size.
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SHA3-256:184e897473fae38b97ddc21ef639a159a85cdc2c7b29f040d779f818ca65929f
User & Date: drh 2019-04-19 23:40:01
Context
2019-04-29
15:46
Soften the criticism of Go because of their decision to omit assert() from the language. check-in: 4a40995c05 user: drh tags: branch-3.28
2019-04-24
17:18
In althttpd.c, disallow a single particular user-agent string that is recently appearing in spider attacks. check-in: 01c0f297c1 user: drh tags: trunk
2019-04-19
23:40
Clarify the documentation on PRAGMA cache_size to explain that the cache size will go up or down in proportion to a change in page size. check-in: 184e897473 user: drh tags: trunk
2019-04-18
16:39
Althttpd now prefers /home over /index.html if it exists. check-in: 87856f6c54 user: drh tags: trunk
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    is limited to 2048000 bytes of memory.
    ^The default suggested cache size can be altered using the
    [SQLITE_DEFAULT_CACHE_SIZE] compile-time options.
    ^The TEMP database has a default suggested cache size of 0 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 abs(N*1024) bytes
    of memory.






    <i>Backwards compatibility note:</i>
    The behavior of cache_size with a negative N
    was different in prior to [version 3.7.10] ([dateof:3.7.10]).  In
    version 3.7.9 and earlier, the number of pages in the cache was set
    to the absolute value of N.</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







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    is limited to 2048000 bytes of memory.
    ^The default suggested cache size can be altered using the
    [SQLITE_DEFAULT_CACHE_SIZE] compile-time options.
    ^The TEMP database has a default suggested cache size of 0 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 be a number of pages that would
    use approximately abs(N*1024) bytes of memory based on the current
    page size.  SQLite remembers the number of pages in the page cache,
    not the amount of memory used.  So if you set the cache size using
    a negative number and subsequently change the page size (using the
    [PRAGMA page_size] command) then the maximum amount of cache
    memory will go up or down in proportion to the change in page size.

    <p><i>Backwards compatibility note:</i>
    The behavior of cache_size with a negative N
    was different prior to [version 3.7.10] ([dateof:3.7.10]).  In
    earlier versions, the number of pages in the cache was set
    to the absolute value of N.</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>


    <p>The default page cache implemention does not allocate
    the full amount of cache memory all at once.  Cache memory
    is allocated in smaller chunks on an as-needed basis.  The page_cache
    setting is a (suggested) upper bound on the amount of memory that the
    cache can use, not the amount of memory it will use all of the time.
    This is the behavior of the default page cache implementation, but an
    [sqlite3_pcache_methods2 | applicaction defined page cache] is free
    to behave differently if it wants.
}

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