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| 9.5.1 Special SQL Variables |
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Certain special variables are set by the <SQL>
statement,
in addition to any columns returned. Like most looping statements,
$loop
and $next
are set.
$loop
The $loop
variable is set at the start of every
iteration of the <SQL>
loop. It is the count of how many
rows were returned so far, not including the current one. When the
<SQL>
loop ends, $loop
is the number of rows
returned. (Ie. up to MAX
rows, but not including SKIP
rows.)
$next
The $next
variable is also set every iteration, but as a
row count from the start of the result set. It is set to the number
of SKIP
rows, plus $loop
(returned rows), plus 1.
Thus it is a useful variable for numbering the result set, as we do
in our patent example, inside the <SQL>
loop in the <search>
function.=SKIP>. At the end of the loop, $next
is the value to use for SKIP
in a new loop to
continue iterating results on the next page.
$indexcount / $rows.min / $rows.max
The $indexcount
variable is set at the start of the first
returned row, to an estimate of the total number of rows
the query will return. The $rows.min
and $rows.max
variables are set similarly, but can be more accurate. These variables
can be used to paginate results, as we'll see later.
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