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Comment:Update the PRAGMA cache_spill documentation to show the new functionality.
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SHA1: 65c5ce0f2100fae1d131a9d492ce5890c285298b
User & Date: drh 2015-11-13 18:14:11
Context
2015-11-25
18:42
Update the documentation for the LIKE/GLOB/REGEXP enhancement to virtual tables. check-in: 6b8138c898 user: drh tags: trunk
2015-11-13
18:14
Update the PRAGMA cache_spill documentation to show the new functionality. check-in: 65c5ce0f21 user: drh tags: trunk
18:04
Begin adding changes to the change log for version 3.10.0. check-in: 5591c0216e user: drh tags: trunk
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Changes to pages/pragma.in.

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    <p>Each database connection can only have a single
    [sqlite3_busy_handler|busy handler].  This PRAGMA sets the busy handler
    for the process, possibly overwriting any previously set busy handler.
}

Pragma cache_spill {
    <p>^(<b>PRAGMA cache_spill;
         <br>PRAGMA cache_spill=</b><i>boolean</i><b>;</b>)^</p>


    <p>^(The cache_spill pragma enables or disables the ability of the pager
    to spill dirty cache pages to the database file in the middle of a 
    transaction.)^  ^(Cache_spill is enabled by default)^ and most applications
    should leave it that way as cache spilling is usually advantageous.
    However, a cache spill has the side-effect of acquiring an
    [EXCLUSIVE lock] on the database file.  Hence, some applications that
    have large long-running transactions may want to disable cache spilling
    in order to prevent the application from acquiring an exclusive lock
    on the database until the moment that the transaction [COMMIT]s.










}

Pragma cache_size {
    <p>^(<b>PRAGMA DB.cache_size;
       <br>PRAGMA DB.cache_size = </b><i>pages</i><b>;
       <br>PRAGMA DB.cache_size = -</b><i>kibibytes</i><b>;</b></p>
    <p>Query or change the suggested maximum number of database disk pages







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    <p>Each database connection can only have a single
    [sqlite3_busy_handler|busy handler].  This PRAGMA sets the busy handler
    for the process, possibly overwriting any previously set busy handler.
}

Pragma cache_spill {
    <p>^(<b>PRAGMA cache_spill;
         <br>PRAGMA cache_spill=</b><i>boolean</i><b>;
         <br>PRAGMA DB.cache_spill=<i>N</i>;</b>)^</p>

    <p>^(The cache_spill pragma enables or disables the ability of the pager
    to spill dirty cache pages to the database file in the middle of a 
    transaction.)^  ^(Cache_spill is enabled by default)^ and most applications
    should leave it that way as cache spilling is usually advantageous.
    However, a cache spill has the side-effect of acquiring an
    [EXCLUSIVE lock] on the database file.  Hence, some applications that
    have large long-running transactions may want to disable cache spilling
    in order to prevent the application from acquiring an exclusive lock
    on the database until the moment that the transaction [COMMIT]s.
    <p>^(The "PRAGMA cache_spill=<i>N</i>" form of this pragma sets a minimum
    cache size threshold required for spilling to occur.  The number of pages
    in cache must exceed both the cache_spill threshold and the maximum cache
    size set by the [PRAGMA cache_size] statement in order for spilling to
    occur.  
    <p>^(The "PRAGMA cache_spill=<i>boolean</i>" form of this pragma applies
    across all databases attached to the database connection.  But the
    "PRAGMA cache_spill=<i>N</i>" form of this statement only applies to
    the "main" schema or whatever other schema is specified as part of the
    statement.
}

Pragma cache_size {
    <p>^(<b>PRAGMA DB.cache_size;
       <br>PRAGMA DB.cache_size = </b><i>pages</i><b>;
       <br>PRAGMA DB.cache_size = -</b><i>kibibytes</i><b>;</b></p>
    <p>Query or change the suggested maximum number of database disk pages