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Posted to notifications@asterixdb.apache.org by "Yingyi Bu (Code Review)" <do...@asterixdb.incubator.apache.org> on 2016/11/24 00:48:38 UTC

Change in asterixdb[master]: Polish the SQL++ reference doc.

Yingyi Bu has uploaded a new change for review.

  https://asterix-gerrit.ics.uci.edu/1358

Change subject: Polish the SQL++ reference doc.
......................................................................

Polish the SQL++ reference doc.

Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
---
M asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
M asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
2 files changed, 41 insertions(+), 24 deletions(-)


  git pull ssh://asterix-gerrit.ics.uci.edu:29418/asterixdb refs/changes/58/1358/1

diff --git a/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md b/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
index f3d4311..3fb3121 100644
--- a/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
+++ b/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
@@ -286,9 +286,8 @@
     FloatLiteral   ::= <DIGITS> ( "f" | "F" )
                      | <DIGITS> ( "." <DIGITS> ( "f" | "F" ) )?
                      | "." <DIGITS> ( "f" | "F" )
-    DoubleLiteral  ::= <DIGITS>
-                     | <DIGITS> ( "." <DIGITS> )?
-                     | "." <DIGITS>
+    DoubleLiteral  ::= <DIGITS> "." <DIGITS>
+                       | "." <DIGITS>
 
 Literals (constants) in SQL++ can be strings, integers, floating point values, double values, boolean constants, or special constant values like `NULL` and `MISSING`. The `NULL` value is like a `NULL` in SQL; it is used to represent an unknown field value. The specialy value `MISSING` is only meaningful in the context of SQL++ field accesses; it occurs when the accessed field simply does not exist at all in a object being accessed.
 
diff --git a/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md b/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
index dc760ba..ed4a8d0 100644
--- a/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
+++ b/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
@@ -96,6 +96,19 @@
 ### <a id="Select_element">SELECT VALUE Clause</a>
 The `SELECT VALUE` clause in SQL++ returns a collection that contains the results of evaluating the `VALUE` expression, with one evaluation being performed per "binding tuple" (i.e., per `FROM` clause item) satisfying the statement's selection criteria.
 For historical reasons SQL++ also allows the keywords `ELEMENT` or `RAW` to be used in place of `VALUE` (not recommended).
+
+The following example shows a standard-alone SELECT.
+
+##### Example
+
+    SELECT VALUE 1;
+
+This query return:
+
+    [
+      1
+    ]
+
 The following example shows a query that selects one user from the GleambookUsers collection.
 
 ##### Example
@@ -745,9 +758,10 @@
 
 ##### Example
 
-    SELECT uid, (SELECT VALUE m.msg FROM msgs m) AS msgs
-    FROM GleambookMessages message
-    GROUP BY message.authorId AS uid GROUP AS msgs(message AS msg);
+       SELECT uid, (SELECT VALUE g.msg FROM g) AS msgs
+       FROM GleambookMessages gbm
+       GROUP BY gbm.authorId AS uid
+       GROUP AS g(gbm as msg);
 
 This variant of the example query returns:
 
@@ -835,9 +849,10 @@
 
 ##### Example
 
-    SELECT uid, msg AS msgs
-    FROM GleambookMessages message
-    GROUP BY message.authorId AS uid GROUP AS msgs(message AS msg);
+       SELECT uid, msg AS msgs
+       FROM GleambookMessages gbm
+       GROUP BY gbm.authorId AS uid
+       GROUP AS g(gbm as msg);
 
 This variant of the query exploits a bit of SQL-style "syntactic sugar" that SQL++ offers to shorten some user queries.
 In particular, in the `SELECT` list, the reference to the `GROUP` variable field `msg` -- because it references a field of the group variable -- is allowed but is "pluralized". As a result, the `msg` reference in the `SELECT` list is
@@ -849,13 +864,14 @@
 ##### Example
 
     SELECT uid,
-           (SELECT VALUE m.msg
-            FROM msgs m
-            WHERE m.msg.message LIKE '% like%'
-            ORDER BY m.msg.messageId
+           (SELECT VALUE g.msg
+            FROM g
+            WHERE g.msg.message LIKE '% like%'
+            ORDER BY g.msg.messageId
             LIMIT 2) AS msgs
-    FROM GleambookMessages message
-    GROUP BY message.authorId AS uid GROUP AS msgs(message AS msg);
+    FROM GleambookMessages gbm
+    GROUP BY gbm.authorId AS uid
+    GROUP AS g(gbm as msg);
 
 This example query returns:
 
@@ -912,14 +928,15 @@
 
 ##### Example
 
-    SELECT authorId,
-       (SELECT VALUE g.msg
-        FROM g
-        WHERE g.msg.message LIKE '% like%'
-        ORDER BY g.msg.messageId
-        LIMIT 2) AS msgs
-    FROM GleambookMessages gbm
-    GROUP BY gbm.authorId GROUP AS g(gbm as msg);
+        SELECT authorId,
+           (SELECT VALUE g.msg
+            FROM g
+            WHERE g.msg.message LIKE '% like%'
+            ORDER BY g.msg.messageId
+            LIMIT 2) AS msgs
+        FROM GleambookMessages gbm
+        GROUP BY gbm.authorId
+        GROUP AS g(gbm as msg);
 
 This query returns:
 
@@ -1020,7 +1037,7 @@
 
 ### <a id="Aggregation_functions">Aggregation functions</a>
 In traditional SQL, which doesn't support nested data, grouping always also involves the use of aggregation
-compute properties of the groups (e.g., the average number of messages per user rather than the actual set
+to compute properties of the groups (e.g., the average number of messages per user rather than the actual set
 of messages per user).
 Each aggregation function in SQL++ takes a collection (e.g., the group of messages) as its input and produces
 a scalar value as its output.
@@ -1548,6 +1565,7 @@
 | Feature |  SQL++ | SQL-92 |  Why different?  |
 |----------|--------|-------|------------------|
 | SELECT * | Returns nested objects | Returns flattened concatenated objects | Nested collections are 1st class citizens |
+| SELECT list | order not preserved | order preserved | Fields in a JSON object is not ordered |
 | Subquery | Returns a collection  | The returned collection is cast into a scalar value if the subquery appears in a SELECT list or on one side of a comparison or as input to a function | Nested collections are 1st class citizens |
 | LEFT OUTER JOIN |  Fills in `MISSING`(s) for non-matches  |   Fills in `NULL`(s) for non-matches    | "Absence" is more appropriate than "unknown" here.  |
 | UNION ALL       | Allows heterogeneous inputs and output | Input streams must be UNION-compatible and output field names are drawn from the first input stream | Heterogenity and nested collections are common |

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Gerrit-Owner: Yingyi Bu <bu...@gmail.com>

Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 3:

Build Started https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-notopic/3355/

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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 3:

Integration Tests Started https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-integration-tests/1169/

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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 1:

Build Started https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-notopic/3353/

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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Yingyi Bu (Code Review)" <do...@asterixdb.incubator.apache.org>.
Yingyi Bu has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 2:

(3 comments)

https://asterix-gerrit.ics.uci.edu/#/c/1358/2/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
File asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md:

Line 761:        SELECT uid, (SELECT VALUE g.msg FROM g) AS msgs
> Why this indentation change?
Done


Line 852:        SELECT uid, msg AS msgs
> Why this indentation change?
Done


Line 931:         SELECT authorId,
> Why this indentation change?
Done


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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 2: Integration-Tests+1

Integration Tests Successful

https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-integration-tests/1168/ : SUCCESS

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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Till Westmann (Code Review)" <do...@asterixdb.incubator.apache.org>.
Till Westmann has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 3: Code-Review+2

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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Till Westmann (Code Review)" <do...@asterixdb.incubator.apache.org>.
Till Westmann has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 2:

(3 comments)

https://asterix-gerrit.ics.uci.edu/#/c/1358/2/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
File asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md:

Line 761:        SELECT uid, (SELECT VALUE g.msg FROM g) AS msgs
Why this indentation change?


Line 852:        SELECT uid, msg AS msgs
Why this indentation change?


Line 931:         SELECT authorId,
Why this indentation change?


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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Yingyi Bu (Code Review)" <do...@asterixdb.incubator.apache.org>.
Yingyi Bu has uploaded a new patch set (#2).

Change subject: Polish the SQL++ reference doc.
......................................................................

Polish the SQL++ reference doc.

Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
---
M asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
M asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
2 files changed, 41 insertions(+), 24 deletions(-)


  git pull ssh://asterix-gerrit.ics.uci.edu:29418/asterixdb refs/changes/58/1358/2
-- 
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Gerrit-Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
Gerrit-PatchSet: 2
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Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Yingyi Bu (Code Review)" <do...@asterixdb.incubator.apache.org>.
Hello Jenkins,

I'd like you to reexamine a change.  Please visit

    https://asterix-gerrit.ics.uci.edu/1358

to look at the new patch set (#3).

Change subject: Polish the SQL++ reference doc.
......................................................................

Polish the SQL++ reference doc.

Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
---
M asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
M asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
2 files changed, 38 insertions(+), 21 deletions(-)


  git pull ssh://asterix-gerrit.ics.uci.edu:29418/asterixdb refs/changes/58/1358/3
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Gerrit-PatchSet: 3
Gerrit-Project: asterixdb
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Gerrit-Owner: Yingyi Bu <bu...@gmail.com>
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Gerrit-Reviewer: Till Westmann <ti...@apache.org>

Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 3:

Integration Tests Successful

https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-integration-tests/1169/ : SUCCESS

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Gerrit-Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
Gerrit-PatchSet: 3
Gerrit-Project: asterixdb
Gerrit-Branch: master
Gerrit-Owner: Yingyi Bu <bu...@gmail.com>
Gerrit-Reviewer: Jenkins <je...@fulliautomatix.ics.uci.edu>
Gerrit-Reviewer: Till Westmann <ti...@apache.org>
Gerrit-Reviewer: Yingyi Bu <bu...@gmail.com>
Gerrit-HasComments: No

Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Yingyi Bu (Code Review)" <do...@asterixdb.incubator.apache.org>.
Yingyi Bu has submitted this change and it was merged.

Change subject: Polish the SQL++ reference doc.
......................................................................


Polish the SQL++ reference doc.

Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
Reviewed-on: https://asterix-gerrit.ics.uci.edu/1358
Sonar-Qube: Jenkins <je...@fulliautomatix.ics.uci.edu>
Tested-by: Jenkins <je...@fulliautomatix.ics.uci.edu>
Reviewed-by: Till Westmann <ti...@apache.org>
---
M asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
M asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
2 files changed, 38 insertions(+), 21 deletions(-)

Approvals:
  Till Westmann: Looks good to me, approved
  Jenkins: Verified; No violations found



diff --git a/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md b/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
index f3d4311..3fb3121 100644
--- a/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
+++ b/asterixdb/asterix-doc/src/main/markdown/sqlpp/2_expr.md
@@ -286,9 +286,8 @@
     FloatLiteral   ::= <DIGITS> ( "f" | "F" )
                      | <DIGITS> ( "." <DIGITS> ( "f" | "F" ) )?
                      | "." <DIGITS> ( "f" | "F" )
-    DoubleLiteral  ::= <DIGITS>
-                     | <DIGITS> ( "." <DIGITS> )?
-                     | "." <DIGITS>
+    DoubleLiteral  ::= <DIGITS> "." <DIGITS>
+                       | "." <DIGITS>
 
 Literals (constants) in SQL++ can be strings, integers, floating point values, double values, boolean constants, or special constant values like `NULL` and `MISSING`. The `NULL` value is like a `NULL` in SQL; it is used to represent an unknown field value. The specialy value `MISSING` is only meaningful in the context of SQL++ field accesses; it occurs when the accessed field simply does not exist at all in a object being accessed.
 
diff --git a/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md b/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
index dc760ba..b90eb06 100644
--- a/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
+++ b/asterixdb/asterix-doc/src/main/markdown/sqlpp/3_query.md
@@ -96,6 +96,19 @@
 ### <a id="Select_element">SELECT VALUE Clause</a>
 The `SELECT VALUE` clause in SQL++ returns a collection that contains the results of evaluating the `VALUE` expression, with one evaluation being performed per "binding tuple" (i.e., per `FROM` clause item) satisfying the statement's selection criteria.
 For historical reasons SQL++ also allows the keywords `ELEMENT` or `RAW` to be used in place of `VALUE` (not recommended).
+
+The following example shows a standard-alone `SELECT VALUE`, which wraps a value into an array.
+
+##### Example
+
+    SELECT VALUE 1;
+
+This query return:
+
+    [
+      1
+    ]
+
 The following example shows a query that selects one user from the GleambookUsers collection.
 
 ##### Example
@@ -745,9 +758,10 @@
 
 ##### Example
 
-    SELECT uid, (SELECT VALUE m.msg FROM msgs m) AS msgs
-    FROM GleambookMessages message
-    GROUP BY message.authorId AS uid GROUP AS msgs(message AS msg);
+    SELECT uid, (SELECT VALUE g.msg FROM g) AS msgs
+    FROM GleambookMessages gbm
+    GROUP BY gbm.authorId AS uid
+    GROUP AS g(gbm as msg);
 
 This variant of the example query returns:
 
@@ -836,8 +850,9 @@
 ##### Example
 
     SELECT uid, msg AS msgs
-    FROM GleambookMessages message
-    GROUP BY message.authorId AS uid GROUP AS msgs(message AS msg);
+    FROM GleambookMessages gbm
+    GROUP BY gbm.authorId AS uid
+    GROUP AS g(gbm as msg);
 
 This variant of the query exploits a bit of SQL-style "syntactic sugar" that SQL++ offers to shorten some user queries.
 In particular, in the `SELECT` list, the reference to the `GROUP` variable field `msg` -- because it references a field of the group variable -- is allowed but is "pluralized". As a result, the `msg` reference in the `SELECT` list is
@@ -849,13 +864,14 @@
 ##### Example
 
     SELECT uid,
-           (SELECT VALUE m.msg
-            FROM msgs m
-            WHERE m.msg.message LIKE '% like%'
-            ORDER BY m.msg.messageId
+           (SELECT VALUE g.msg
+            FROM g
+            WHERE g.msg.message LIKE '% like%'
+            ORDER BY g.msg.messageId
             LIMIT 2) AS msgs
-    FROM GleambookMessages message
-    GROUP BY message.authorId AS uid GROUP AS msgs(message AS msg);
+    FROM GleambookMessages gbm
+    GROUP BY gbm.authorId AS uid
+    GROUP AS g(gbm as msg);
 
 This example query returns:
 
@@ -913,13 +929,14 @@
 ##### Example
 
     SELECT authorId,
-       (SELECT VALUE g.msg
-        FROM g
-        WHERE g.msg.message LIKE '% like%'
-        ORDER BY g.msg.messageId
-        LIMIT 2) AS msgs
+           (SELECT VALUE g.msg
+            FROM g
+            WHERE g.msg.message LIKE '% like%'
+            ORDER BY g.msg.messageId
+            LIMIT 2) AS msgs
     FROM GleambookMessages gbm
-    GROUP BY gbm.authorId GROUP AS g(gbm as msg);
+    GROUP BY gbm.authorId
+    GROUP AS g(gbm as msg);
 
 This query returns:
 
@@ -1020,7 +1037,7 @@
 
 ### <a id="Aggregation_functions">Aggregation functions</a>
 In traditional SQL, which doesn't support nested data, grouping always also involves the use of aggregation
-compute properties of the groups (e.g., the average number of messages per user rather than the actual set
+to compute properties of the groups (e.g., the average number of messages per user rather than the actual set
 of messages per user).
 Each aggregation function in SQL++ takes a collection (e.g., the group of messages) as its input and produces
 a scalar value as its output.
@@ -1548,6 +1565,7 @@
 | Feature |  SQL++ | SQL-92 |  Why different?  |
 |----------|--------|-------|------------------|
 | SELECT * | Returns nested objects | Returns flattened concatenated objects | Nested collections are 1st class citizens |
+| SELECT list | order not preserved | order preserved | Fields in a JSON object is not ordered |
 | Subquery | Returns a collection  | The returned collection is cast into a scalar value if the subquery appears in a SELECT list or on one side of a comparison or as input to a function | Nested collections are 1st class citizens |
 | LEFT OUTER JOIN |  Fills in `MISSING`(s) for non-matches  |   Fills in `NULL`(s) for non-matches    | "Absence" is more appropriate than "unknown" here.  |
 | UNION ALL       | Allows heterogeneous inputs and output | Input streams must be UNION-compatible and output field names are drawn from the first input stream | Heterogenity and nested collections are common |

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Gerrit-Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
Gerrit-PatchSet: 4
Gerrit-Project: asterixdb
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Gerrit-Owner: Yingyi Bu <bu...@gmail.com>
Gerrit-Reviewer: Jenkins <je...@fulliautomatix.ics.uci.edu>
Gerrit-Reviewer: Till Westmann <ti...@apache.org>
Gerrit-Reviewer: Yingyi Bu <bu...@gmail.com>

Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 2:

Integration Tests Started https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-integration-tests/1168/

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Gerrit-MessageType: comment
Gerrit-Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
Gerrit-PatchSet: 2
Gerrit-Project: asterixdb
Gerrit-Branch: master
Gerrit-Owner: Yingyi Bu <bu...@gmail.com>
Gerrit-Reviewer: Jenkins <je...@fulliautomatix.ics.uci.edu>
Gerrit-Reviewer: Till Westmann <ti...@apache.org>
Gerrit-HasComments: No

Change in asterixdb[master]: Polish the SQL++ reference doc.

Posted by "Jenkins (Code Review)" <do...@asterixdb.incubator.apache.org>.
Jenkins has posted comments on this change.

Change subject: Polish the SQL++ reference doc.
......................................................................


Patch Set 2:

Build Started https://asterix-jenkins.ics.uci.edu/job/asterix-gerrit-notopic/3354/

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To view, visit https://asterix-gerrit.ics.uci.edu/1358
To unsubscribe, visit https://asterix-gerrit.ics.uci.edu/settings

Gerrit-MessageType: comment
Gerrit-Change-Id: Ifb3cc23ebbf9e390d6eabf9386b15550aa5d6d43
Gerrit-PatchSet: 2
Gerrit-Project: asterixdb
Gerrit-Branch: master
Gerrit-Owner: Yingyi Bu <bu...@gmail.com>
Gerrit-Reviewer: Jenkins <je...@fulliautomatix.ics.uci.edu>
Gerrit-HasComments: No