cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From tylerho...@apache.org
Subject svn commit: r1757419 [16/29] - in /cassandra/site/src/doc: ./ 3.10/ 3.10/_images/ 3.10/_sources/ 3.10/_sources/architecture/ 3.10/_sources/configuration/ 3.10/_sources/cql/ 3.10/_sources/data_modeling/ 3.10/_sources/development/ 3.10/_sources/faq/ 3.10...
Date Tue, 23 Aug 2016 19:25:18 GMT
Added: cassandra/site/src/doc/3.10/cql/definitions.html
URL: http://svn.apache.org/viewvc/cassandra/site/src/doc/3.10/cql/definitions.html?rev=1757419&view=auto
==============================================================================
--- cassandra/site/src/doc/3.10/cql/definitions.html (added)
+++ cassandra/site/src/doc/3.10/cql/definitions.html Tue Aug 23 19:25:17 2016
@@ -0,0 +1,314 @@
+---
+layout: docpage
+
+title: "Documentation"
+
+is_homepage: false
+is_sphinx_doc: true
+
+doc-parent: "The Cassandra Query Language (CQL)"
+
+doc-title: "Definitions"
+doc-header-links: '
+  <link rel="top" title="Apache Cassandra Documentation v3.10" href="../index.html"/>
+      <link rel="up" title="The Cassandra Query Language (CQL)" href="index.html"/>
+      <link rel="next" title="Data Types" href="types.html"/>
+      <link rel="prev" title="The Cassandra Query Language (CQL)" href="index.html"/>
+'
+doc-search-path: "../search.html"
+
+extra-footer: '
+<script type="text/javascript">
+    var DOCUMENTATION_OPTIONS = {
+      URL_ROOT:    "",
+      VERSION:     "",
+      COLLAPSE_INDEX: false,
+      FILE_SUFFIX: ".html",
+      HAS_SOURCE:  false,
+      SOURCELINK_SUFFIX: ""
+    };
+</script>
+'
+
+---
+<div class="container-fluid">
+  <div class="row">
+    <div class="col-md-2">
+      <div class="doc-navigation">
+        <div class="doc-menu" role="navigation">
+          <div class="navbar-header">
+            <button type="button" class="pull-left navbar-toggle" data-toggle="collapse"
data-target=".sidebar-navbar-collapse">
+              <span class="sr-only">Toggle navigation</span>
+              <span class="icon-bar"></span>
+              <span class="icon-bar"></span>
+              <span class="icon-bar"></span>
+            </button>
+          </div>
+          <div class="navbar-collapse collapse sidebar-navbar-collapse">
+            <form id="doc-search-form" class="navbar-form" action="../search.html" method="get"
role="search">
+              <div class="form-group">
+                <input type="text" size="30" class="form-control input-sm" name="q" placeholder="Search
docs">
+                <input type="hidden" name="check_keywords" value="yes" />
+                <input type="hidden" name="area" value="default" />
+              </div>
+            </form>
+            
+            
+            
+            <ul class="current">
+<li class="toctree-l1"><a class="reference internal" href="../getting_started/index.html">Getting
Started</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../architecture/index.html">Architecture</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../data_modeling/index.html">Data
Modeling</a></li>
+<li class="toctree-l1 current"><a class="reference internal" href="index.html">The
Cassandra Query Language (CQL)</a><ul class="current">
+<li class="toctree-l2 current"><a class="current reference internal" href="#">Definitions</a><ul>
+<li class="toctree-l3"><a class="reference internal" href="#conventions">Conventions</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#identifiers">Identifiers
and keywords</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#constants">Constants</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#terms">Terms</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#comments">Comments</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#statements">Statements</a></li>
+<li class="toctree-l3"><a class="reference internal" href="#prepared-statements">Prepared
Statements</a></li>
+</ul>
+</li>
+<li class="toctree-l2"><a class="reference internal" href="types.html">Data Types</a></li>
+<li class="toctree-l2"><a class="reference internal" href="ddl.html">Data Definition</a></li>
+<li class="toctree-l2"><a class="reference internal" href="dml.html">Data Manipulation</a></li>
+<li class="toctree-l2"><a class="reference internal" href="indexes.html">Secondary
Indexes</a></li>
+<li class="toctree-l2"><a class="reference internal" href="mvs.html">Materialized
Views</a></li>
+<li class="toctree-l2"><a class="reference internal" href="security.html">Security</a></li>
+<li class="toctree-l2"><a class="reference internal" href="functions.html">Functions</a></li>
+<li class="toctree-l2"><a class="reference internal" href="json.html">JSON Support</a></li>
+<li class="toctree-l2"><a class="reference internal" href="triggers.html">Triggers</a></li>
+<li class="toctree-l2"><a class="reference internal" href="appendices.html">Appendices</a></li>
+<li class="toctree-l2"><a class="reference internal" href="changes.html">Changes</a></li>
+</ul>
+</li>
+<li class="toctree-l1"><a class="reference internal" href="../configuration/index.html">Configuring
Cassandra</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../operating/index.html">Operating
Cassandra</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../tools/index.html">Cassandra
Tools</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../troubleshooting/index.html">Troubleshooting</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../development/index.html">Cassandra
Development</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../faq/index.html">Frequently
Asked Questions</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../bugs.html">Reporting
Bugs and Contributing</a></li>
+<li class="toctree-l1"><a class="reference internal" href="../contactus.html">Contact
us</a></li>
+</ul>
+
+            
+            
+          </div><!--/.nav-collapse -->
+        </div>
+      </div>
+    </div>
+    <div class="col-md-8">
+      <div class="content doc-content">
+        <div class="container">
+          
+  <div class="section" id="definitions">
+<h1>Definitions<a class="headerlink" href="#definitions" title="Permalink to this
headline">¶</a></h1>
+<div class="section" id="conventions">
+<span id="id1"></span><h2>Conventions<a class="headerlink" href="#conventions"
title="Permalink to this headline">¶</a></h2>
+<p>To aid in specifying the CQL syntax, we will use the following conventions in this
document:</p>
+<ul class="simple">
+<li>Language rules will be given in an informal <a class="reference external" href="http://en.wikipedia.org/wiki/Backus%E2%80%93Naur_Form#Variants">BNF
variant</a> notation. In particular, we&#8217;ll use square brakets
+(<code class="docutils literal"><span class="pre">[</span> <span class="pre">item</span>
<span class="pre">]</span></code>) for optional items, <code class="docutils
literal"><span class="pre">*</span></code> and <code class="docutils
literal"><span class="pre">+</span></code> for repeated items (where
<code class="docutils literal"><span class="pre">+</span></code> imply
at least one).</li>
+<li>The grammar will also use the following convention for convenience: non-terminal
term will be lowercase (and link to
+their definition) while terminal keywords will be provided &#8220;all caps&#8221;.
Note however that keywords are
+<a class="reference internal" href="#identifiers"><span class="std std-ref">Identifiers
and keywords</span></a> and are thus case insensitive in practice. We will also
define some early construction using
+regexp, which we&#8217;ll indicate with <code class="docutils literal"><span
class="pre">re(&lt;some</span> <span class="pre">regular</span> <span
class="pre">expression&gt;)</span></code>.</li>
+<li>The grammar is provided for documentation purposes and leave some minor details
out.  For instance, the comma on the
+last column definition in a <code class="docutils literal"><span class="pre">CREATE</span>
<span class="pre">TABLE</span></code> statement is optional but supported
if present even though the grammar in
+this document suggests otherwise. Also, not everything accepted by the grammar is necessarily
valid CQL.</li>
+<li>References to keywords or pieces of CQL code in running text will be shown in a
<code class="docutils literal"><span class="pre">fixed-width</span> <span
class="pre">font</span></code>.</li>
+</ul>
+</div>
+<div class="section" id="identifiers">
+<span id="identifiers-and-keywords"></span><h2>Identifiers and keywords<a
class="headerlink" href="#identifiers" title="Permalink to this headline">¶</a></h2>
+<p>The CQL language uses <em>identifiers</em> (or <em>names</em>)
to identify tables, columns and other objects. An identifier is a token
+matching the regular expression <code class="docutils literal"><span class="pre">[a-zA-Z][a-zA-Z0-9_]*</span></code>.</p>
+<p>A number of such identifiers, like <code class="docutils literal"><span
class="pre">SELECT</span></code> or <code class="docutils literal"><span
class="pre">WITH</span></code>, are <em>keywords</em>. They have
a fixed meaning for the language
+and most are reserved. The list of those keywords can be found in <a class="reference
internal" href="appendices.html#appendix-a"><span class="std std-ref">Appendix A:
CQL Keywords</span></a>.</p>
+<p>Identifiers and (unquoted) keywords are case insensitive. Thus <code class="docutils
literal"><span class="pre">SELECT</span></code> is the same than <code
class="docutils literal"><span class="pre">select</span></code> or <code
class="docutils literal"><span class="pre">sElEcT</span></code>, and
+<code class="docutils literal"><span class="pre">myId</span></code>
is the same than <code class="docutils literal"><span class="pre">myid</span></code>
or <code class="docutils literal"><span class="pre">MYID</span></code>.
A convention often used (in particular by the samples of this
+documentation) is to use upper case for keywords and lower case for other identifiers.</p>
+<p>There is a second kind of identifiers called <em>quoted identifiers</em>
defined by enclosing an arbitrary sequence of
+characters (non empty) in double-quotes(<code class="docutils literal"><span class="pre">&quot;</span></code>).
Quoted identifiers are never keywords. Thus <code class="docutils literal"><span
class="pre">&quot;select&quot;</span></code> is not a
+reserved keyword and can be used to refer to a column (note that using this is particularly
advised), while <code class="docutils literal"><span class="pre">select</span></code>
+would raise a parsing error. Also, contrarily to unquoted identifiers and keywords, quoted
identifiers are case
+sensitive (<code class="docutils literal"><span class="pre">&quot;My</span>
<span class="pre">Quoted</span> <span class="pre">Id&quot;</span></code>
is <em>different</em> from <code class="docutils literal"><span class="pre">&quot;my</span>
<span class="pre">quoted</span> <span class="pre">id&quot;</span></code>).
A fully lowercase quoted identifier that matches
+<code class="docutils literal"><span class="pre">[a-zA-Z][a-zA-Z0-9_]*</span></code>
is however <em>equivalent</em> to the unquoted identifier obtained by removing
the double-quote (so
+<code class="docutils literal"><span class="pre">&quot;myid&quot;</span></code>
is equivalent to <code class="docutils literal"><span class="pre">myid</span></code>
and to <code class="docutils literal"><span class="pre">myId</span></code>
but different from <code class="docutils literal"><span class="pre">&quot;myId&quot;</span></code>).
 Inside a quoted identifier, the
+double-quote character can be repeated to escape it, so <code class="docutils literal"><span
class="pre">&quot;foo</span> <span class="pre">&quot;&quot;</span>
<span class="pre">bar&quot;</span></code> is a valid identifier.</p>
+<div class="admonition note">
+<p class="first admonition-title">Note</p>
+<p class="last"><em>quoted identifiers</em> allows to declare columns with
arbitrary names, and those can sometime clash with
+specific names used by the server. For instance, when using conditional update, the server
will respond with a
+result-set containing a special result named <code class="docutils literal"><span
class="pre">&quot;[applied]&quot;</span></code>. If you’ve declared
a column with such a name, this
+could potentially confuse some tools and should be avoided. In general, unquoted identifiers
should be preferred but
+if you use quoted identifiers, it is strongly advised to avoid any name enclosed by squared
brackets (like
+<code class="docutils literal"><span class="pre">&quot;[applied]&quot;</span></code>)
and any name that looks like a function call (like <code class="docutils literal"><span
class="pre">&quot;f(x)&quot;</span></code>).</p>
+</div>
+<p>More formally, we have:</p>
+<pre>
+<strong id="grammar-token-identifier">identifier         </strong> ::=  <a
class="reference internal" href="#grammar-token-unquoted_identifier"><code class="xref
docutils literal"><span class="pre">unquoted_identifier</span></code></a>
| <a class="reference internal" href="#grammar-token-quoted_identifier"><code class="xref
docutils literal"><span class="pre">quoted_identifier</span></code></a>
+<strong id="grammar-token-unquoted_identifier">unquoted_identifier</strong> ::=
 re('[a-zA-Z][a-zA-Z0-9_]*')
+<strong id="grammar-token-quoted_identifier">quoted_identifier  </strong> ::=
 '&quot;' (any character where &quot; can appear if doubled)+ '&quot;'
+</pre>
+</div>
+<div class="section" id="constants">
+<span id="id2"></span><h2>Constants<a class="headerlink" href="#constants"
title="Permalink to this headline">¶</a></h2>
+<p>CQL defines the following kind of <em>constants</em>:</p>
+<pre>
+<strong id="grammar-token-constant">constant</strong> ::=  <a class="reference
internal" href="#grammar-token-string"><code class="xref docutils literal"><span
class="pre">string</span></code></a> | <a class="reference internal"
href="#grammar-token-integer"><code class="xref docutils literal"><span class="pre">integer</span></code></a>
| <a class="reference internal" href="#grammar-token-float"><code class="xref docutils
literal"><span class="pre">float</span></code></a> | <a class="reference
internal" href="#grammar-token-boolean"><code class="xref docutils literal"><span
class="pre">boolean</span></code></a> | <a class="reference internal"
href="#grammar-token-uuid"><code class="xref docutils literal"><span class="pre">uuid</span></code></a>
| <a class="reference internal" href="#grammar-token-blob"><code class="xref docutils
literal"><span class="pre">blob</span></code></a> | NULL
+<strong id="grammar-token-string">string  </strong> ::=  '\'' (any character
where ' can appear if doubled)+ '\''
+              '$$' (any character other than '$$') '$$'
+<strong id="grammar-token-integer">integer </strong> ::=  re('-?[0-9]+')
+<strong id="grammar-token-float">float   </strong> ::=  re('-?[0-9]+(\.[0-9]*)?([eE][+-]?[0-9+])?')
| NAN | INFINITY
+<strong id="grammar-token-boolean">boolean </strong> ::=  TRUE | FALSE
+<strong id="grammar-token-uuid">uuid    </strong> ::=  <a class="reference
internal" href="#grammar-token-hex"><code class="xref docutils literal"><span
class="pre">hex</span></code></a>{8}-<a class="reference internal"
href="#grammar-token-hex"><code class="xref docutils literal"><span class="pre">hex</span></code></a>{4}-<a
class="reference internal" href="#grammar-token-hex"><code class="xref docutils literal"><span
class="pre">hex</span></code></a>{4}-<a class="reference internal"
href="#grammar-token-hex"><code class="xref docutils literal"><span class="pre">hex</span></code></a>{4}-<a
class="reference internal" href="#grammar-token-hex"><code class="xref docutils literal"><span
class="pre">hex</span></code></a>{12}
+<strong id="grammar-token-hex">hex     </strong> ::=  re(&quot;[0-9a-fA-F]&quot;)
+<strong id="grammar-token-blob">blob    </strong> ::=  '0' ('x' | 'X') <a
class="reference internal" href="#grammar-token-hex"><code class="xref docutils literal"><span
class="pre">hex</span></code></a>+
+</pre>
+<p>In other words:</p>
+<ul class="simple">
+<li>A string constant is an arbitrary sequence of characters enclosed by single-quote(<code
class="docutils literal"><span class="pre">'</span></code>). A single-quote
+can be included by repeating it, e.g. <code class="docutils literal"><span class="pre">'It''s</span>
<span class="pre">raining</span> <span class="pre">today'</span></code>.
Those are not to be confused with quoted
+<a class="reference internal" href="#identifiers"><span class="std std-ref">Identifiers
and keywords</span></a> that use double-quotes. Alternatively, a string can be
defined by enclosing the arbitrary sequence
+of characters by two dollar characters, in which case single-quote can be use without escaping
(<code class="docutils literal"><span class="pre">$$It's</span> <span
class="pre">raining</span>
+<span class="pre">today$$</span></code>). That latter form is often used
when defining <a class="reference internal" href="functions.html#udfs"><span class="std
std-ref">user-defined functions</span></a> to avoid having to
+escape single-quote characters in function body (as they are more likely to occur than <code
class="docutils literal"><span class="pre">$$</span></code>).</li>
+<li>Integer, float and boolean constant are defined as expected. Note however than
float allows the special <code class="docutils literal"><span class="pre">NaN</span></code>
and
+<code class="docutils literal"><span class="pre">Infinity</span></code>
constants.</li>
+<li>CQL supports <a class="reference external" href="https://en.wikipedia.org/wiki/Universally_unique_identifier">UUID</a>
constants.</li>
+<li>Blobs content are provided in hexadecimal and prefixed by <code class="docutils
literal"><span class="pre">0x</span></code>.</li>
+<li>The special <code class="docutils literal"><span class="pre">NULL</span></code>
constant denotes the absence of value.</li>
+</ul>
+<p>For how these constants are typed, see the <a class="reference internal" href="types.html#data-types"><span
class="std std-ref">Data Types</span></a> section.</p>
+</div>
+<div class="section" id="terms">
+<h2>Terms<a class="headerlink" href="#terms" title="Permalink to this headline">¶</a></h2>
+<p>CQL has the notion of a <em>term</em>, which denotes the kind of values
that CQL support. Terms are defined by:</p>
+<pre>
+<strong id="grammar-token-term">term         </strong> ::=  <a class="reference
internal" href="#grammar-token-constant"><code class="xref docutils literal"><span
class="pre">constant</span></code></a> | <a class="reference internal"
href="#grammar-token-literal"><code class="xref docutils literal"><span class="pre">literal</span></code></a>
| <a class="reference internal" href="#grammar-token-function_call"><code class="xref
docutils literal"><span class="pre">function_call</span></code></a>
| <a class="reference internal" href="#grammar-token-type_hint"><code class="xref
docutils literal"><span class="pre">type_hint</span></code></a>
| <a class="reference internal" href="#grammar-token-bind_marker"><code class="xref
docutils literal"><span class="pre">bind_marker</span></code></a>
+<strong id="grammar-token-literal">literal      </strong> ::=  <a class="reference
internal" href="types.html#grammar-token-collection_literal"><code class="xref docutils
literal"><span class="pre">collection_literal</span></code></a>
| <a class="reference internal" href="types.html#grammar-token-udt_literal"><code
class="xref docutils literal"><span class="pre">udt_literal</span></code></a>
| <a class="reference internal" href="types.html#grammar-token-tuple_literal"><code
class="xref docutils literal"><span class="pre">tuple_literal</span></code></a>
+<strong id="grammar-token-function_call">function_call</strong> ::=  <a class="reference
internal" href="#grammar-token-identifier"><code class="xref docutils literal"><span
class="pre">identifier</span></code></a> '(' [ <a class="reference
internal" href="#grammar-token-term"><code class="xref docutils literal"><span
class="pre">term</span></code></a> (',' <a class="reference internal"
href="#grammar-token-term"><code class="xref docutils literal"><span class="pre">term</span></code></a>)*
] ')'
+<strong id="grammar-token-type_hint">type_hint    </strong> ::=  '(' <a class="reference
internal" href="types.html#grammar-token-cql_type"><code class="xref docutils literal"><span
class="pre">cql_type</span></code></a> `)` term
+<strong id="grammar-token-bind_marker">bind_marker  </strong> ::=  '?' | ':'
<a class="reference internal" href="#grammar-token-identifier"><code class="xref
docutils literal"><span class="pre">identifier</span></code></a>
+</pre>
+<p>A term is thus one of:</p>
+<ul class="simple">
+<li>A <a class="reference internal" href="#constants"><span class="std std-ref">constant</span></a>.</li>
+<li>A literal for either <a class="reference internal" href="types.html#collections"><span
class="std std-ref">a collection</span></a>, <a class="reference internal"
href="types.html#udts"><span class="std std-ref">a user-defined type</span></a>
or <a class="reference internal" href="types.html#tuples"><span class="std std-ref">a
tuple</span></a>
+(see the linked sections for details).</li>
+<li>A function call: see <a class="reference internal" href="functions.html#cql-functions"><span
class="std std-ref">the section on functions</span></a> for details on which
<a class="reference internal" href="functions.html#native-functions"><span class="std
std-ref">native function</span></a> exists and how to define your own <a
class="reference internal" href="functions.html#udfs"><span class="std std-ref">user-defined
ones</span></a>.</li>
+<li>A <em>type hint</em>: see the <span class="xref std std-ref">related
section</span> for details.</li>
+<li>A bind marker, which denotes a variable to be bound at execution time. See the
section on <a class="reference internal" href="#prepared-statements"><span class="std
std-ref">Prepared Statements</span></a>
+for details. A bind marker can be either anonymous (<code class="docutils literal"><span
class="pre">?</span></code>) or named (<code class="docutils literal"><span
class="pre">:some_name</span></code>). The latter form provides a more
+convenient way to refer to the variable for binding it and should generally be preferred.</li>
+</ul>
+</div>
+<div class="section" id="comments">
+<h2>Comments<a class="headerlink" href="#comments" title="Permalink to this headline">¶</a></h2>
+<p>A comment in CQL is a line beginning by either double dashes (<code class="docutils
literal"><span class="pre">--</span></code>) or double slash (<code
class="docutils literal"><span class="pre">//</span></code>).</p>
+<p>Multi-line comments are also supported through enclosure within <code class="docutils
literal"><span class="pre">/*</span></code> and <code class="docutils
literal"><span class="pre">*/</span></code> (but nesting is not supported).</p>
+<div class="highlight-cql"><div class="highlight"><pre><span></span><span
class="c1">-- This is a comment</span>
+<span class="c1">// This is a comment too</span>
+<span class="cm">/* This is</span>
+<span class="cm">   a multi-line comment */</span>
+</pre></div>
+</div>
+</div>
+<div class="section" id="statements">
+<h2>Statements<a class="headerlink" href="#statements" title="Permalink to this
headline">¶</a></h2>
+<p>CQL consists of statements that can be divided in the following categories:</p>
+<ul class="simple">
+<li><a class="reference internal" href="ddl.html#data-definition"><span class="std
std-ref">Data Definition</span></a> statements, to define and change how the
data is stored (keyspaces and tables).</li>
+<li><a class="reference internal" href="dml.html#data-manipulation"><span
class="std std-ref">Data Manipulation</span></a> statements, for selecting,
inserting and deleting data.</li>
+<li><a class="reference internal" href="indexes.html#secondary-indexes"><span
class="std std-ref">Secondary Indexes</span></a> statements.</li>
+<li><a class="reference internal" href="mvs.html#materialized-views"><span
class="std std-ref">Materialized Views</span></a> statements.</li>
+<li><a class="reference internal" href="security.html#cql-roles"><span class="std
std-ref">Database Roles</span></a> statements.</li>
+<li><a class="reference internal" href="security.html#cql-permissions"><span
class="std std-ref">Permissions</span></a> statements.</li>
+<li><a class="reference internal" href="functions.html#udfs"><span class="std
std-ref">User-Defined Functions</span></a> statements.</li>
+<li><a class="reference internal" href="types.html#udts"><span class="std
std-ref">User-Defined Types</span></a> statements.</li>
+<li><a class="reference internal" href="triggers.html#cql-triggers"><span
class="std std-ref">Triggers</span></a> statements.</li>
+</ul>
+<p>All the statements are listed below and are described in the rest of this documentation
(see links above):</p>
+<pre>
+<strong id="grammar-token-cql_statement">cql_statement               </strong>
::=  <a class="reference internal" href="#grammar-token-statement"><code class="xref
docutils literal"><span class="pre">statement</span></code></a>
[ ';' ]
+<strong id="grammar-token-statement">statement                   </strong> ::=
 <a class="reference internal" href="#grammar-token-ddl_statement"><code class="xref
docutils literal"><span class="pre">ddl_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-dml_statement"><code
class="xref docutils literal"><span class="pre">dml_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-secondary_index_statement"><code
class="xref docutils literal"><span class="pre">secondary_index_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-materialized_view_statement"><code
class="xref docutils literal"><span class="pre">materialized_view_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-role_or_permission_statement"><code
class="xref docutils literal"><span class="pre">role_or_permission_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-udf_statement"><code
class="xref docutils literal"><span class="pre">udf_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-udt_statement"><code
class="xref docutils literal"><span class="pre">udt_statement</span></code></a>
+                                  | <a class="reference internal" href="#grammar-token-trigger_statement"><code
class="xref docutils literal"><span class="pre">trigger_statement</span></code></a>
+<strong id="grammar-token-ddl_statement">ddl_statement               </strong>
::=  <a class="reference internal" href="ddl.html#grammar-token-use_statement"><code
class="xref docutils literal"><span class="pre">use_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-create_keyspace_statement"><code
class="xref docutils literal"><span class="pre">create_keyspace_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-alter_keyspace_statement"><code
class="xref docutils literal"><span class="pre">alter_keyspace_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-drop_keyspace_statement"><code
class="xref docutils literal"><span class="pre">drop_keyspace_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-create_table_statement"><code
class="xref docutils literal"><span class="pre">create_table_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-alter_table_statement"><code
class="xref docutils literal"><span class="pre">alter_table_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-drop_table_statement"><code
class="xref docutils literal"><span class="pre">drop_table_statement</span></code></a>
+                                  | <a class="reference internal" href="ddl.html#grammar-token-truncate_statement"><code
class="xref docutils literal"><span class="pre">truncate_statement</span></code></a>
+<strong id="grammar-token-dml_statement">dml_statement               </strong>
::=  <a class="reference internal" href="dml.html#grammar-token-select_statement"><code
class="xref docutils literal"><span class="pre">select_statement</span></code></a>
+                                  | <a class="reference internal" href="dml.html#grammar-token-insert_statement"><code
class="xref docutils literal"><span class="pre">insert_statement</span></code></a>
+                                  | <a class="reference internal" href="dml.html#grammar-token-update_statement"><code
class="xref docutils literal"><span class="pre">update_statement</span></code></a>
+                                  | <a class="reference internal" href="dml.html#grammar-token-delete_statement"><code
class="xref docutils literal"><span class="pre">delete_statement</span></code></a>
+                                  | <a class="reference internal" href="dml.html#grammar-token-batch_statement"><code
class="xref docutils literal"><span class="pre">batch_statement</span></code></a>
+<strong id="grammar-token-secondary_index_statement">secondary_index_statement   </strong>
::=  <a class="reference internal" href="indexes.html#grammar-token-create_index_statement"><code
class="xref docutils literal"><span class="pre">create_index_statement</span></code></a>
+                                  | <a class="reference internal" href="indexes.html#grammar-token-drop_index_statement"><code
class="xref docutils literal"><span class="pre">drop_index_statement</span></code></a>
+<strong id="grammar-token-materialized_view_statement">materialized_view_statement
</strong> ::=  <a class="reference internal" href="mvs.html#grammar-token-create_materialized_view_statement"><code
class="xref docutils literal"><span class="pre">create_materialized_view_statement</span></code></a>
+                                  | <a class="reference internal" href="mvs.html#grammar-token-drop_materialized_view_statement"><code
class="xref docutils literal"><span class="pre">drop_materialized_view_statement</span></code></a>
+<strong id="grammar-token-role_or_permission_statement">role_or_permission_statement</strong>
::=  <a class="reference internal" href="security.html#grammar-token-create_role_statement"><code
class="xref docutils literal"><span class="pre">create_role_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-alter_role_statement"><code
class="xref docutils literal"><span class="pre">alter_role_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-drop_role_statement"><code
class="xref docutils literal"><span class="pre">drop_role_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-grant_role_statement"><code
class="xref docutils literal"><span class="pre">grant_role_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-revoke_role_statement"><code
class="xref docutils literal"><span class="pre">revoke_role_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-list_roles_statement"><code
class="xref docutils literal"><span class="pre">list_roles_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-grant_permission_statement"><code
class="xref docutils literal"><span class="pre">grant_permission_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-revoke_permission_statement"><code
class="xref docutils literal"><span class="pre">revoke_permission_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-list_permissions_statement"><code
class="xref docutils literal"><span class="pre">list_permissions_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-create_user_statement"><code
class="xref docutils literal"><span class="pre">create_user_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-alter_user_statement"><code
class="xref docutils literal"><span class="pre">alter_user_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-drop_user_statement"><code
class="xref docutils literal"><span class="pre">drop_user_statement</span></code></a>
+                                  | <a class="reference internal" href="security.html#grammar-token-list_users_statement"><code
class="xref docutils literal"><span class="pre">list_users_statement</span></code></a>
+<strong id="grammar-token-udf_statement">udf_statement               </strong>
::=  <a class="reference internal" href="functions.html#grammar-token-create_function_statement"><code
class="xref docutils literal"><span class="pre">create_function_statement</span></code></a>
+                                  | <a class="reference internal" href="functions.html#grammar-token-drop_function_statement"><code
class="xref docutils literal"><span class="pre">drop_function_statement</span></code></a>
+                                  | <a class="reference internal" href="functions.html#grammar-token-create_aggregate_statement"><code
class="xref docutils literal"><span class="pre">create_aggregate_statement</span></code></a>
+                                  | <a class="reference internal" href="functions.html#grammar-token-drop_aggregate_statement"><code
class="xref docutils literal"><span class="pre">drop_aggregate_statement</span></code></a>
+<strong id="grammar-token-udt_statement">udt_statement               </strong>
::=  <a class="reference internal" href="types.html#grammar-token-create_type_statement"><code
class="xref docutils literal"><span class="pre">create_type_statement</span></code></a>
+                                  | <a class="reference internal" href="types.html#grammar-token-alter_type_statement"><code
class="xref docutils literal"><span class="pre">alter_type_statement</span></code></a>
+                                  | <a class="reference internal" href="types.html#grammar-token-drop_type_statement"><code
class="xref docutils literal"><span class="pre">drop_type_statement</span></code></a>
+<strong id="grammar-token-trigger_statement">trigger_statement           </strong>
::=  <a class="reference internal" href="triggers.html#grammar-token-create_trigger_statement"><code
class="xref docutils literal"><span class="pre">create_trigger_statement</span></code></a>
+                                  | <a class="reference internal" href="triggers.html#grammar-token-drop_trigger_statement"><code
class="xref docutils literal"><span class="pre">drop_trigger_statement</span></code></a>
+</pre>
+</div>
+<div class="section" id="prepared-statements">
+<span id="id3"></span><h2>Prepared Statements<a class="headerlink" href="#prepared-statements"
title="Permalink to this headline">¶</a></h2>
+<p>CQL supports <em>prepared statements</em>. Prepared statements are an
optimization that allows to parse a query only once but
+execute it multiple times with different concrete values.</p>
+<p>Any statement that uses at least one bind marker (see <a class="reference internal"
href="#grammar-token-bind_marker"><code class="xref std std-token docutils literal"><span
class="pre">bind_marker</span></code></a>) will need to be <em>prepared</em>.
After which the statement
+can be <em>executed</em> by provided concrete values for each of its marker.
The exact details of how a statement is prepared
+and then executed depends on the CQL driver used and you should refer to your driver documentation.</p>
+</div>
+</div>
+
+
+
+          
+          <div class="doc-prev-next-links" role="navigation" aria-label="footer navigation">
+            
+            <a href="types.html" class="btn btn-default pull-right " role="button" title="Data
Types" accesskey="n">Next <span class="glyphicon glyphicon-circle-arrow-right" aria-hidden="true"></span></a>
+            
+            
+            <a href="index.html" class="btn btn-default" role="button" title="The Cassandra
Query Language (CQL)" accesskey="p"><span class="glyphicon glyphicon-circle-arrow-left"
aria-hidden="true"></span> Previous</a>
+            
+          </div>
+          
+        </div>
+      </div>
+    </div>
+    <div class="col-md-2">
+    </div>
+  </div>
+</div>
\ No newline at end of file



Mime
View raw message