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ROWS clause
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Function:
Allow to limit a number of rows retrieved from a select expression. For a highest level
select statement, it would mean a number of rows sent to the host program.

Author:
Dmitry Yemanov <yemanov@yandex.ru>

Syntax rules:
SELECT ... [ORDER BY <expr_list>] ROWS <expr1> [TO <expr2>]

Scope:
DSQL, PSQL

Example(s):
1. SELECT * FROM T1
UNION ALL
SELECT * FROM T2
ORDER BY COL
ROWS 10 TO 100
2. SELECT COL1, COL2, ( SELECT COL3 FROM T3 ORDER BY COL4 DESC ROWS 1 )
FROM T4
3. DELETE FROM T5
ORDER BY COL5
ROWS 1

Note(s):
1. ROWS is a more understandable alternative to the FIRST/SKIP clauses with some extra benefits.
It can be used in unions and all kind of subqueries. Also it's available in the UPDATE/DELETE
statements.
2. When <expr2> is omitted, then ROWS <expr1> is a semantical equivalent for FIRST <expr1>. When
both <expr1> and <expr2> are used, then ROWS <expr1> TO <expr2> means:
FIRST (<expr2> - <expr1> + 1) SKIP (<expr1> - 1). Note that there's no semantical equivalent
for a SKIP clause used without a FIRST clause.