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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"><html><head><title>SQLite Virtual Machine Opcodes</title><style type="text/css">body {    margin: auto;    font-family: "Verdana" "sans-serif";    padding: 8px 1%;}a { color: #45735f }a:visited { color: #734559 }.logo { position:absolute; margin:3px; }.tagline {  float:right;  text-align:right;  font-style:italic;  width:240px;  margin:12px;  margin-top:58px;}.toolbar {  font-variant: small-caps;  text-align: center;  line-height: 1.6em;  margin: 0;  padding:1px 8px;}.toolbar a { color: white; text-decoration: none; padding: 6px 12px; }.toolbar a:visited { color: white; }.toolbar a:hover { color: #80a796; background: white; }.content    { margin: 5%; }.content dt { font-weight:bold; }.content dd { margin-bottom: 25px; margin-left:20%; }.content ul { padding:0px; padding-left: 15px; margin:0px; }/* rounded corners */.se  { background: url(images/se.png) 100% 100% no-repeat #80a796}.sw  { background: url(images/sw.png) 0% 100% no-repeat }.ne  { background: url(images/ne.png) 100% 0% no-repeat }.nw  { background: url(images/nw.png) 0% 0% no-repeat }</style><meta http-equiv="content-type" content="text/html; charset=UTF-8">  </head><body><div><!-- container div to satisfy validator --><a href="index.html"><img class="logo" src="images/SQLite.gif" alt="SQLite Logo" border="0"></a><div><!-- IE hack to prevent disappearing logo--></div><div class="tagline">Small. Fast. Reliable.<br>Choose any three.</div><table width=100% style="clear:both"><tr><td>  <div class="se"><div class="sw"><div class="ne"><div class="nw">  <div class="toolbar">    <a href="about.html">About</a>    <a href="sitemap.html">Sitemap</a>    <a href="docs.html">Documentation</a>    <a href="download.html">Download</a>    <a href="copyright.html">License</a>    <a href="news.html">News</a>    <a href="http://www.sqlite.org/cvstrac/index">Developers</a>    <a href="support.html">Support</a>  </div></div></div></div></div></td></tr></table>  <h2>SQLite Virtual Machine Opcodes</h2><h3>Introduction</h3><p>In order to execute an SQL statement, the SQLite library first parsesthe SQL, analyzes the statement, then generates a short program to executethe statement.  The program is generated for a "virtual machine" implementedby the SQLite library.  This document describes the operation of thatvirtual machine.</p><p>This document is intended as a reference, not a tutorial.A separate <a href="vdbe.html">Virtual Machine Tutorial</a> is available.  If you are looking for a narrative descriptionof how the virtual machine works, you should read the tutorialand not this document.  Once you have a basic idea of what thevirtual machine does, you can refer back to this document forthe details on a particular opcode.Unfortunately, the virtual machine tutorial was written forSQLite version 1.0.  There are substantial changes in the virtualmachine for version 2.0 and and again for version 3.0.0 and againfor version 3.5.5 and the document has not been updated.  But thebasic concepts behind the virtual machine still apply.</p><p>The source code to the virtual machine is in the <b>vdbe.c</b> sourcefile.  All of the opcode definitions further down in this document arecontained in comments in the source file.  In fact, the opcode tablein this documentwas generated by scanning the <b>vdbe.c</b> source file and extracting the necessary information from comments.  So the source code comments are really the canonical source of informationabout the virtual machine.  When in doubt, refer to the source code.</p><p>Each instruction in the virtual machine consists of an opcode andup to five operands named P1, P2  P3, P4, and P5.  P1, P2, and P3 are 32-bit signed integers.  These operands often refer to registers.P2 is always thejump destination in any operation that might cause a jump.P4 may be a 32-bit signed integer, a 64-bit signed integer, a64-bit floating point value, a string literal, a Blob literal,a pointer to a collating sequence comparison function, or apointer to the implemantation of an application-defined SQLfunction, or various other things.  P5 is an unsigned characternormally used as a flag.Some operators use all five operands.  Some useone or two.  Some operators use none of the operands.<p><p>The virtual machine begins execution on instruction number 0.Execution continues until a Halt instruction is seen, or the program counter becomes one greater than the address oflast instruction, or there is an execution error.When the virtual machine halts, all memorythat it allocated is released and all database cursors it mayhave had open are closed.  If the execution stopped due to anerror, any pending transactions are terminated and changes madeto the database are rolled back.</p><p>The virtual machine can have zero or more cursors.  Each cursoris a pointer into a single table or index within the database.There can be multiple cursors pointing at the same index or table.All cursors operate independently, even cursors pointing to the sameindices or tables.The only way for the virtual machine to interact with a databasefile is through a cursor.Instructions in the virtualmachine can create a new cursor (OpenRead or OpenWrite),read data from a cursor(Column), advance the cursor to the next entry in the table(Next) or index (NextIdx), and many other operations.All cursors are automaticallyclosed when the virtual machine terminates.</p><p>The virtual machine contains an arbitrary number of registerslocations with addresses beginning at one and growing upward.Each memory location can hold an arbitrary string.  The registershold all intermediate results of a calculation.</p><h3>Viewing Programs Generated By SQLite</h3><p>Every SQL statement that SQLite interprets results in a programfor the virtual machine.  But if you precede the SQL statement withthe keyword "EXPLAIN" the virtual machine will not execute theprogram.  Instead, the instructions of the program will be returnedlike a query result.  This feature is useful for debugging andfor learning how the virtual machine operates.</p><p>You can use the <b>sqlite3.exe</b> command-line interface (CLI)tool to see theinstructions generated by an SQL statement.  The following isan example:</p><blockquote><tt>$&nbsp;<b>sqlite3&nbsp;ex1.db</b><br>sqlite&gt;&nbsp;<b>.explain</b><br>sqlite&gt;&nbsp;<b>explain&nbsp;delete&nbsp;from&nbsp;tbl1&nbsp;where&nbsp;two&lt;20;</b><br>addr&nbsp;&nbsp;opcode&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;p1&nbsp;&nbsp;&nbsp;&nbsp;p2&nbsp;&nbsp;&nbsp;&nbsp;p3&nbsp;&nbsp;&nbsp;&nbsp;p4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;p5&nbsp;&nbsp;comment<br>----&nbsp;&nbsp;-------------&nbsp;&nbsp;----&nbsp;&nbsp;----&nbsp;&nbsp;----&nbsp;&nbsp;---------&nbsp;&nbsp;--&nbsp;&nbsp;-------<br>0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Trace&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;explain..&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Goto&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;20&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;OpenRead&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;tbl&nbsp;&nbsp;&nbsp;&nbsp;<br>3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;SetNumColumns&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Rewind&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;11&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Column&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;tbl.two<br>6&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Integer&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;20&nbsp;&nbsp;&nbsp;&nbsp;3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>7&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Ge&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;cs(BINARY)&nbsp;6a&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>8&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Rowid&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>9&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;FifoWrite&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>10&nbsp;&nbsp;&nbsp;&nbsp;Next&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>11&nbsp;&nbsp;&nbsp;&nbsp;Close&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>12&nbsp;&nbsp;&nbsp;&nbsp;OpenWrite&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;tbl&nbsp;&nbsp;&nbsp;&nbsp;<br>13&nbsp;&nbsp;&nbsp;&nbsp;SetNumColumns&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>14&nbsp;&nbsp;&nbsp;&nbsp;FifoRead&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;18&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>15&nbsp;&nbsp;&nbsp;&nbsp;NotExists&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;17&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>16&nbsp;&nbsp;&nbsp;&nbsp;Delete&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;tbl&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>17&nbsp;&nbsp;&nbsp;&nbsp;Goto&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;14&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>18&nbsp;&nbsp;&nbsp;&nbsp;Close&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>19&nbsp;&nbsp;&nbsp;&nbsp;Halt&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>20&nbsp;&nbsp;&nbsp;&nbsp;Transaction&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>21&nbsp;&nbsp;&nbsp;&nbsp;VerifyCookie&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>22&nbsp;&nbsp;&nbsp;&nbsp;TableLock&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;-1&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;tbl&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br>23&nbsp;&nbsp;&nbsp;&nbsp;Goto&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;00</tt></blockquote><p>All you have to do is add the "EXPLAIN" keyword to the front of theSQL statement.  But if you use the ".explain" command in the CLI,it will set up the output mode to make the program more easilyviewable.</p><p>Depending on compile-time options, you can put the SQLite virtual machine in a mode where it will trace itsexecution by writing messages to standard output.  The non-standardSQL "PRAGMA" comments can be used to turn tracing on and off.  Toturn tracing on, enter:</p><blockquote><pre>PRAGMA vdbe_trace=on;</pre></blockquote><p>You can turn tracing back off by entering a similar statement butchanging the value "on" to "off".</p><h3>The Opcodes</h3><p>There are currently 129opcodes defined by the virtual machine.All currently defined opcodes are described in the table below.This table was generated automatically by scanning the source codefrom the file <b>vdbe.c</b>.</p><p><table cellspacing="1" border="1" cellpadding="10"><tr><th>Opcode&nbsp;Name</th><th>Description</th></tr><tr><td valign="top" align="center"><a name="Add"></a><p>Add</p><td><p>Add the value in register P1 to the value in register P2and store the result in regiser P3.If either input is NULL, the result is NULL.</td></tr><tr><td valign="top" align="center"><a name="AddImm"></a><p>AddImm</p><td><p>Add the constant P2 the value in register P1.The result is always an integer.</p><p>To force any register to be an integer, just add 0.</td></tr><tr><td valign="top" align="center"><a name="Affinity"></a><p>Affinity</p><td><p>Apply affinities to a range of P2 registers starting with P1.</p><p>P4 is a string that is P2 characters long. The nth character of thestring indicates the column affinity that should be used for the nthmemory cell in the range.</td></tr><tr><td valign="top" align="center"><a name="AggFinal"></a><p>AggFinal</p><td><p>Execute the finalizer function for an aggregate.  P1 isthe memory location that is the accumulator for the aggregate.</p>
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