Documentation Source Text

and extracting the necessary information from comments.  So the 
source code comments are really the canonical source of information
about the virtual machine.  When in doubt, refer to the source code.</p>

<p>Each instruction in the virtual machine consists of an opcode and
up to five operands named P1, P2  P3, P4, and P5.  The P1, P2, and P3 
operands are 32-bit signed integers.  These operands often refer to 
registers but can also be used for other purposes.  The P1 operand is
usually the cursor number for opcodes that operate on cursors.
P2 is usually the jump destination jump instructions.
P4 may be a 32-bit signed integer, a 64-bit signed integer, a
64-bit floating point value, a string literal, a Blob literal,
a pointer to a collating sequence comparison function, or a
pointer to the implementation of an application-defined SQL
function, or various other things.  P5 is an unsigned character

(Column), advance the cursor to the next entry in the table
(Next) or index (NextIdx), and many other operations.
All cursors are automatically
closed when the virtual machine terminates.</p>

<p>The virtual machine contains an arbitrary number of registers
with addresses beginning at one and growing upward.
Each register can hold a single SQL value (a string, a BLOB, a signed 64-bit
integer, a 64-bit floating point number, or a NULL).  A register might
also hold objects used internally by SQLite, such as a RowSet or Frame.
</p>

<h3>Viewing Programs Generated By SQLite</h3>

<p>Every SQL statement that SQLite interprets results in a program