update to latest and truncate long queries in ui

data/test/tabletserver/exec_cases.txt

@@ -4,7 +4,16 @@
   "PlanID": "PASS_SELECT",
   "TableName": "",
   "FieldQuery": "select * from a where 1 != 1 union select * from b where 1 != 1",
-  "FullQuery": "select * from a union select * from b"
+  "FullQuery": "select * from a union select * from b limit :#maxLimit"
+}
+
+# union with limit
+"select * from a union select * from b limit 10"
+{
+  "PlanID": "PASS_SELECT",
+  "TableName": "",
+  "FieldQuery": "select * from a where 1 != 1 union select * from b where 1 != 1",
+  "FullQuery": "select * from a union select * from b limit 10"
 }
 
 # distinct

doc/ServerConfiguration.md

@@ -147,7 +147,9 @@ Vitess servers are written in Go. There are a few Vitess-specific knobs that app
 
 ### Go version
 
-Go, being a young language, tends to add major improvements over each version. So, the latest Go version is almost always recommended. The current version to use Go 1.6.
+Go, being a young language, tends to add major improvements over each version.
+So, the latest Go version is almost always recommended.
+Note that the latest Go version may be higher than the minimum version we require for compiling the binaries (see ["Prerequisites" section in the Getting Started guide](/getting-started/#prerequisites)).
 
 ### GOMAXPROCS
 

docs/user-guide/row-based-replication.html

@@ -318,27 +318,31 @@ <h2 id="mysql-row-based-replication">MySQL Row Based Replication</h2>
 <p>The
 <a href="https://dev.mysql.com/doc/refman/5.7/en/replication-options-binary-log.html#sysvar_binlog_row_image"><code class="prettyprint">binlog-row-image</code> option</a> can
 be used to control which rows are used to identify the columns for the Update
-and Delete Rows events. The default setting for that option is to log all columns.</p>
+and Delete Rows events. The default setting for that option is to log all
+columns.</p>
 
-<h2 id="vitess-use-of-replication-stream">Vitess Use of Replication Stream</h2>
+<h2 id="vitess-use-of-mysql-replication-stream">Vitess Use of MySQL Replication Stream</h2>
 
 <p>Vitess uses the Replication Stream in a number of places. This part explains how
-we can use RBR for these.</p>
+we use RBR for these.</p>
 
 <h3 id="vttablet-replication-stream-watcher">vttablet Replication Stream Watcher</h3>
 
-<p>This is enabled by the <code class="prettyprint">watch_replication_stream</code> option, and is used by <a href="/user-guide/update-stream.html">Update
-Stream</a>. It only cares about the GTIDs for the events, so it is unaffected by the use of RBR.</p>
+<p>This is enabled by the <code class="prettyprint">watch_replication_stream</code> option, and is used
+by <a href="/user-guide/update-stream.html">Update Stream</a>. It only cares about the
+GTIDs for the events, so it is unaffected by the use of RBR.</p>
 
 <p><em>Note</em>: the current vttablet also reloads the schema when it sees a DDL in the
-stream. See below for more information on this.</p>
+stream. See below for more information on this. DDLs are however not represented
+in RBR, so this is an orthogonal issue.</p>
 
 <h3 id="update-stream">Update Stream</h3>
 
 <p>The current implementation uses comments in the original SQL (in SQR) to provide
 the primary key of the column that is being changed.</p>
 
-<p>We are changing this to also parse the RBR events, and extract the primary key value.</p>
+<p>We are changing this to also parse the RBR events, and extract the primary key
+value.</p>
 
 <p><em>Note</em>: this means we need accurate schema information. See below.</p>
 
@@ -405,6 +409,28 @@ <h3 id="applying-schema-changes">Applying Schema Changes</h3>
 can be parsed correctly in all cases.</p></li>
 </ul>
 
+<h2 id="unsupported-features">Unsupported Features</h2>
+
+<p>This part describes the features that are not supported for RBR in Vitess as of
+March 2017:</p>
+
+<ul>
+<li><p><em>Fractional timestamps for MariaDB</em>: not supported. This affects the objects
+of type <code class="prettyprint">TIMESTAMP</code>, <code class="prettyprint">TIME</code> and <code class="prettyprint">DATETIME</code>. The way that feature is
+implemented in MariaDB, the binary logs do not contain enough information to
+be parsed, but instead MariaDB relies on the schema knowledge. This is very
+fragile. MySQL 5.6+ added new data types, and these are supported.</p></li>
+<li><p><em>JSON type in MySQL 5.7+</em>: the representation of these in the binlogs is a
+blob containing indexed binary data. Re-building the SQL version of the data,
+so it can be re-inserted during resharding, is not supported yet. It wouldn&#39;t
+however be a lot of work, with other libraries also supporting this, and the
+C++ MySQL code being well written and easy to read. See for instance
+<a href="https://github.com/shyiko/mysql-binlog-connector-java/pull/119">https://github.com/shyiko/mysql-binlog-connector-java/pull/119</a></p></li>
+<li><p><em>Timezones support</em>: the binary logs store timestamps in UTC. When converting
+these to SQL, we print the UTC value. If the server is not in UTC, that will
+result in data corruption. <em>Note</em>: we are working on a fix for that one.</p></li>
+</ul>
+
 <h2 id="update-stream-extensions">Update Stream Extensions</h2>
 
 <p><a href="/user-guide/update-stream.html">Update Stream</a> can be changed to contain both
@@ -427,8 +453,8 @@ <h2 id="vttablet-simplifications">Vttablet Simplifications</h2>
 modified rows, to rewrite the queries in an efficient way and tag each statement
 with the Primary Key. None of this may be necessary with RBR.</p>
 
-<p>We plan to eventually add a <code class="prettyprint">rbr_mode</code> flag to vttablet to disable all the things it can
-skip if RBR is used.</p>
+<p>We plan to eventually add a <code class="prettyprint">rbr_mode</code> flag to vttablet to disable all the
+things it can skip if RBR is used.</p>
 
       </div>
     </div>

docs/user-guide/server-configuration.html

@@ -443,7 +443,9 @@ <h2 id="vitess-servers">Vitess servers</h2>
 
 <h3 id="go-version">Go version</h3>
 
-<p>Go, being a young language, tends to add major improvements over each version. So, the latest Go version is almost always recommended. The current version to use Go 1.6.</p>
+<p>Go, being a young language, tends to add major improvements over each version.
+So, the latest Go version is almost always recommended.
+Note that the latest Go version may be higher than the minimum version we require for compiling the binaries (see <a href="/getting-started/#prerequisites">&quot;Prerequisites&quot; section in the Getting Started guide</a>).</p>
 
 <h3 id="gomaxprocs">GOMAXPROCS</h3>