[GitHub] trafodion pull request #1458: [TRAFODION-2973] Add syntax and examples of *[...

[liuyu000 <gi...@git.apache.org>]

Github user liuyu000 commented on a diff in the pull request:

    https://github.com/apache/trafodion/pull/1458#discussion_r171451317
  
    --- Diff: docs/sql_reference/src/asciidoc/_chapters/sql_statements.adoc ---
    @@ -6989,20 +6989,22 @@ By abstracting the complicated parts of the query into simpler, separate and log
     +
     specifies the unique name of the CTE to be created, which is a valid SQL identifier with a maximum of 128 characters. Duplicate names are not allowed in a single with-clause.
     
    -* `"[" ANY _N_ "]" | "[" FIRST _N_ "]"`
    +* `"[" ANY _N_ "]" | "[" FIRST _N_ "]" | "[" LAST _N_ "]" `
     +
     specifies that _N_ rows are to be returned (assuming the table has at least _N_ rows and that the qualification
     criteria specified in the WHERE clause, if any, would select at least _N_ rows) and you do not care which _N_ rows
     are chosen (out of the qualified rows) to actually be returned.
     +
    -_You must enclose ANY N or FIRST N in square brackets ([])._ The quotation marks ("") around each square bracket in
    +You must enclose `ANY _N_`, `FIRST _N_` or `LAST _N_` in square brackets ([]). The quotation marks ("") around each square bracket in
     the syntax diagram indicate that the bracket is a required character that you must type as shown (for example, [ANY 10]
     or [FIRST 5]). Do not include quotation marks in ANY or FIRST clauses.
     +
     [FIRST _N_] is different from [ANY _N_] only if you use ORDER BY on any of the columns in the select list to sort the
     result table of the SELECT statement. _N_ is an unsigned numeric literal with no scale. If _N_ is greater than the number
     of rows in the table, all rows are returned. [ANY _N_] and [FIRST _N_] are disallowed in nested SELECT statements and on
     either side of a UNION operation.
    ++
    +`[LAST _N_]` performs a full table scan and calculates elapsed time. The _N_ must be 0 or 1. `[LAST _0_]` does not return any rows. `[LAST _1_]` returns only the last qualified row.
    --- End diff --
    
    Thanks for your explanations! Your comments have been incorporated. :)


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