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SHA1 Hash:a577a4e61897524f894f62aaaff35d22a9213ed5
Date: 2013-05-23 11:48:55
User: drh
Comment:Update the documentation for PRAGMA mmap_size to explain that it can sometimes be a no-op.
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       start-time limit has been set.</p>

    <p>The [PRAGMA mmap_size] statement will never increase the amount
       of address space used for memory-mapped I/O above the
       hard limit set by the [SQLITE_MAX_MMAP_SIZE] compile-time option,
       nor the hard limit set start-time by the second argument to
       sqlite3_config([SQLITE_CONFIG_MMAP_SIZE])</p>







}

Pragma page_size {
   <p>^(<b>PRAGMA page_size;
       <br>PRAGMA page_size = </b><i>bytes</i><b>;</b></p>
    <p>Query or set the page size of the database.)^ ^The page
    size must be a power of two between 512 and 65536 inclusive.







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       start-time limit has been set.</p>

    <p>The [PRAGMA mmap_size] statement will never increase the amount
       of address space used for memory-mapped I/O above the
       hard limit set by the [SQLITE_MAX_MMAP_SIZE] compile-time option,
       nor the hard limit set start-time by the second argument to
       sqlite3_config([SQLITE_CONFIG_MMAP_SIZE])</p>

    <p>The size of the memory-mapped I/O region cannot be changed while
       the memory-mapped I/O region is in active use, to avoid unmapping
       memory out from under running SQL statements.  For this reason,
       the mmap_size pragma may be a no-op if the prior mmap_size is non-zero
       and there are other SQL statements running concurrently on the same
       [database connection].</p>
}

Pragma page_size {
   <p>^(<b>PRAGMA page_size;
       <br>PRAGMA page_size = </b><i>bytes</i><b>;</b></p>
    <p>Query or set the page size of the database.)^ ^The page
    size must be a power of two between 512 and 65536 inclusive.