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+
+ <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’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 “all caps”. 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’ll indicate with <code class="docutils literal"><span class="pre">re(<some</span> <span class="pre">regular</span> <span class="pre">expression>)</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">"</span></code>). Quoted identifiers are never keywords. Thus <code class="docutils literal"><span class="pre">"select"</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">"My</span> <span class="pre">Quoted</span> <span class="pre">Id"</span></code> is <em>different</em> from <code class="docutils literal"><span class="pre">"my</span> <span class="pre">quoted</span> <span class="pre">id"</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">"myid"</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">"myId"</span></code>). Inside a quoted identifier, the
+double-quote character can be repeated to escape it, so <code class="docutils literal"><span class="pre">"foo</span> <span class="pre">""</span> <span class="pre">bar"</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">"[applied]"</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">"[applied]"</span></code>) and any name that looks like a function call (like <code class="docutils literal"><span class="pre">"f(x)"</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> ::= '"' (any character where " can appear if doubled)+ '"'
+</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("[0-9a-fA-F]")
+<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>
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