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From buyin...@apache.org
Subject incubator-asterixdb git commit: Fix AQL doc for SQL fans.
Date Thu, 01 Oct 2015 01:13:58 GMT
Repository: incubator-asterixdb
Updated Branches:
  refs/heads/master 9a12c9503 -> 3db1397c3


Fix AQL doc for SQL fans.

Change-Id: I36b94af0280909ba49eca4ad311db3a633b305b9
Reviewed-on: https://asterix-gerrit.ics.uci.edu/420
Tested-by: Ian Maxon <imaxon@apache.org>
Tested-by: Jenkins <jenkins@fulliautomatix.ics.uci.edu>
Reviewed-by: Till Westmann <tillw@apache.org>


Project: http://git-wip-us.apache.org/repos/asf/incubator-asterixdb/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-asterixdb/commit/3db1397c
Tree: http://git-wip-us.apache.org/repos/asf/incubator-asterixdb/tree/3db1397c
Diff: http://git-wip-us.apache.org/repos/asf/incubator-asterixdb/diff/3db1397c

Branch: refs/heads/master
Commit: 3db1397c3ac877e7ef3f85373e3e446729c8dc0c
Parents: 9a12c95
Author: Yingyi Bu <buyingyi@gmail.com>
Authored: Wed Sep 30 17:27:47 2015 -0700
Committer: Yingyi Bu <buyingyi@gmail.com>
Committed: Wed Sep 30 18:11:18 2015 -0700

----------------------------------------------------------------------
 .../src/site/markdown/aql/primer-sql-like.md      | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-asterixdb/blob/3db1397c/asterix-doc/src/site/markdown/aql/primer-sql-like.md
----------------------------------------------------------------------
diff --git a/asterix-doc/src/site/markdown/aql/primer-sql-like.md b/asterix-doc/src/site/markdown/aql/primer-sql-like.md
index 1d560e2..0debb94 100644
--- a/asterix-doc/src/site/markdown/aql/primer-sql-like.md
+++ b/asterix-doc/src/site/markdown/aql/primer-sql-like.md
@@ -353,7 +353,7 @@ FLWOR is an acronym that is short for _for_-_let_-_where_-_order by_-_return_,
 naming five of the most frequently used clauses from the syntax of a full AQL query.
 AQL also includes _group by_ and _limit_ clauses, as you will see shortly.
 Roughly speaking, for SQL afficiandos, the _for_ clause in AQL is like the _from_ clause
in SQL,
-the _return_ clause in AQL is like the _return_ clause in SQL (but appears at the end instead
of
+the _return_ clause in AQL is like the _select_ clause in SQL (but appears at the end instead
of
 the beginning of a query), the _let_ clause in AQL is like SQL's _with_ clause, and the _where_
 and _order by_ clauses in both languages are similar.
 
@@ -374,10 +374,10 @@ Suppose the user we want is the user whose id is 8:
         where $user.id = 8
         select $user;
 
-The query's _for_ clause  binds the variable `$user` incrementally to the data instances
residing in
+The query's _from_ clause  binds the variable `$user` incrementally to the data instances
residing in
 the dataset named FacebookUsers.
 Its _where_ clause selects only those bindings having a user id of interest, filtering out
the rest.
-The _return_ clause returns the (entire) data instance for each binding that satisfies the
predicate.
+The _select_ clause returns the (entire) data instance for each binding that satisfies the
predicate.
 Since this dataset is indexed on user id (its primary key), this query will be done via a
quick index lookup.
 
 The expected result for our sample data is as follows:
@@ -510,7 +510,7 @@ The query result for our sample data in this case is:
         { "uname": "SuzannaTillson", "message": " like iphone the voicemail-service is awesome"
}
 
 
-(It is worth knowing, with respect to influencing AsterixDB's query evaluation, that nested
_for_
+(It is worth knowing, with respect to influencing AsterixDB's query evaluation, that nested
_from_
 clauses---a.k.a. joins--- are currently evaluated with the "outer" clause probing the data
of the "inner"
 clause.)
 
@@ -707,14 +707,14 @@ For every Twitter user, the following group-by/aggregate query counts
the number
         "count": count($t)
         };
 
-The _for_ clause incrementally binds $t to tweets, and the _group by_ clause groups the tweets
by its
+The _from_ clause incrementally binds $t to tweets, and the _group by_ clause groups the
tweets by its
 issuer's Twitter screen-name.
 Unlike SQL, where data is tabular---flat---the data model underlying AQL allows for nesting.
-Thus, following the _group by_ clause, the _return_ clause in this query sees a sequence
of $t groups,
+Thus, following the _group by_ clause, the _select_ clause in this query sees a sequence
of $t groups,
 with each such group having an associated $uid variable value (i.e., the tweeting user's
screen name).
-In the context of the return clause, due to "... with $t ...", $uid is bound to the tweeter's
id and $t
+In the context of the _select_ clause, due to "... keeping $t ...", $uid is bound to the
tweeter's id and $t
 is bound to the _set_ of tweets issued by that tweeter.
-The return clause constructs a result record containing the tweeter's user id and the count
of the items
+The _select_ clause constructs a result record containing the tweeter's user id and the count
of the items
 in the associated tweet set.
 The query result will contain one such record per screen name.
 This query also illustrates another feature of AQL; notice that each user's screen name is
accessed via a
@@ -769,7 +769,7 @@ The following AQL  query returns the top 3 Twitter users based on who
has issued
 
         from $t in dataset TweetMessages
         group by $uid := $t.user.screen-name keeping $t
-        let $c := count($t)
+        with $c := count($t)
         order by $c desc
         limit 3
         select {


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