summaryrefslogtreecommitdiffstats
path: root/www/csv.html
diff options
context:
space:
mode:
Diffstat (limited to 'www/csv.html')
-rw-r--r--www/csv.html240
1 files changed, 240 insertions, 0 deletions
diff --git a/www/csv.html b/www/csv.html
new file mode 100644
index 0000000..1b87759
--- /dev/null
+++ b/www/csv.html
@@ -0,0 +1,240 @@
+<!DOCTYPE html>
+<html><head>
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<meta http-equiv="content-type" content="text/html; charset=UTF-8">
+<link href="sqlite.css" rel="stylesheet">
+<title>The CSV Virtual Table</title>
+<!-- path= -->
+</head>
+<body>
+<div class=nosearch>
+<a href="index.html">
+<img class="logo" src="images/sqlite370_banner.gif" alt="SQLite" border="0">
+</a>
+<div><!-- IE hack to prevent disappearing logo --></div>
+<div class="tagline desktoponly">
+Small. Fast. Reliable.<br>Choose any three.
+</div>
+<div class="menu mainmenu">
+<ul>
+<li><a href="index.html">Home</a>
+<li class='mobileonly'><a href="javascript:void(0)" onclick='toggle_div("submenu")'>Menu</a>
+<li class='wideonly'><a href='about.html'>About</a>
+<li class='desktoponly'><a href="docs.html">Documentation</a>
+<li class='desktoponly'><a href="download.html">Download</a>
+<li class='wideonly'><a href='copyright.html'>License</a>
+<li class='desktoponly'><a href="support.html">Support</a>
+<li class='desktoponly'><a href="prosupport.html">Purchase</a>
+<li class='search' id='search_menubutton'>
+<a href="javascript:void(0)" onclick='toggle_search()'>Search</a>
+</ul>
+</div>
+<div class="menu submenu" id="submenu">
+<ul>
+<li><a href='about.html'>About</a>
+<li><a href='docs.html'>Documentation</a>
+<li><a href='download.html'>Download</a>
+<li><a href='support.html'>Support</a>
+<li><a href='prosupport.html'>Purchase</a>
+</ul>
+</div>
+<div class="searchmenu" id="searchmenu">
+<form method="GET" action="search">
+<select name="s" id="searchtype">
+<option value="d">Search Documentation</option>
+<option value="c">Search Changelog</option>
+</select>
+<input type="text" name="q" id="searchbox" value="">
+<input type="submit" value="Go">
+</form>
+</div>
+</div>
+<script>
+function toggle_div(nm) {
+var w = document.getElementById(nm);
+if( w.style.display=="block" ){
+w.style.display = "none";
+}else{
+w.style.display = "block";
+}
+}
+function toggle_search() {
+var w = document.getElementById("searchmenu");
+if( w.style.display=="block" ){
+w.style.display = "none";
+} else {
+w.style.display = "block";
+setTimeout(function(){
+document.getElementById("searchbox").focus()
+}, 30);
+}
+}
+function div_off(nm){document.getElementById(nm).style.display="none";}
+window.onbeforeunload = function(e){div_off("submenu");}
+/* Disable the Search feature if we are not operating from CGI, since */
+/* Search is accomplished using CGI and will not work without it. */
+if( !location.origin || !location.origin.match || !location.origin.match(/http/) ){
+document.getElementById("search_menubutton").style.display = "none";
+}
+/* Used by the Hide/Show button beside syntax diagrams, to toggle the */
+function hideorshow(btn,obj){
+var x = document.getElementById(obj);
+var b = document.getElementById(btn);
+if( x.style.display!='none' ){
+x.style.display = 'none';
+b.innerHTML='show';
+}else{
+x.style.display = '';
+b.innerHTML='hide';
+}
+return false;
+}
+var antiRobot = 0;
+function antiRobotGo(){
+if( antiRobot!=3 ) return;
+antiRobot = 7;
+var j = document.getElementById("mtimelink");
+if(j && j.hasAttribute("data-href")) j.href=j.getAttribute("data-href");
+}
+function antiRobotDefense(){
+document.body.onmousedown=function(){
+antiRobot |= 2;
+antiRobotGo();
+document.body.onmousedown=null;
+}
+document.body.onmousemove=function(){
+antiRobot |= 2;
+antiRobotGo();
+document.body.onmousemove=null;
+}
+setTimeout(function(){
+antiRobot |= 1;
+antiRobotGo();
+}, 100)
+antiRobotGo();
+}
+antiRobotDefense();
+</script>
+<div class=fancy>
+<div class=nosearch>
+<div class="fancy_title">
+The CSV Virtual Table
+</div>
+</div>
+
+
+
+
+<h1 id="overview"><span>1. </span>Overview</h1>
+
+<p>
+The CSV virtual table reads
+<a href="https://www.ietf.org/rfc/rfc4180.txt">RFC 4180</a> formatted comma-separated
+values, and returns that content as if it were rows and columns of an SQL
+table.
+</p>
+
+<p>
+The CSV virtual table is useful to applications that need to bulk-load
+large amounts of comma-separated value content.
+The CSV virtual table is also useful as a template source file for
+implementing other virtual tables.
+</p>
+
+
+<p>
+The CSV virtual table is not built into the SQLite amalgamation.
+It is available as a
+<a href="https://www.sqlite.org/src/artifact?ci=trunk&filename=ext/misc/csv.c">separate source file</a>
+that can be compiled into a <a href="loadext.html">loadable extension</a>.
+Typical usage of the CSV virtual table from the
+<a href="cli.html">command-line shell</a> would be something like this:
+
+</p><div class="codeblock"><pre>.load ./csv
+CREATE VIRTUAL TABLE temp.t1 USING csv(filename='thefile.csv');
+SELECT * FROM t1;
+</pre></div>
+
+<p>
+The first line of the script above causes the <a href="cli.html">command-line shell</a> to
+read and activate the run-time loadable extension for CSV. For an
+application, the equivalent C-language API is
+<a href="c3ref/load_extension.html">sqlite3_load_extension()</a>.
+Observe that the filename extension (ex: ".dll" or ".so" or ".dylib") is
+omitted from the extension filename. Omitting the filename extension is
+not required, but it helps in making the script cross-platform. SQLite
+will automatically append the appropriate extension.
+
+</p><p>
+The second line above creates a virtual table named "t1" that reads
+the content of the file named in the argument. The number and names of
+the columns is determined automatically by reading the first line of
+content. Other options to the CSV virtual table provide the ability to
+take the CSV content from a string rather than a separate file, and give
+the programmer more control over the number and names of the columns.
+The options are detailed below. The CSV virtual table is usually
+created as a TEMP table so that it exists only for the current database
+connection and does not become a permanent part of the database schema.
+Note that there is no "CREATE TEMP VIRTUAL TABLE" command in SQLite.
+Instead, prepend the "temp." schema prefix to the name of the virtual
+table.
+
+</p><p>
+The third line of the example shows the virtual table being used, to read
+all content of the CSV file. This is perhaps the simplest possible use
+of the virtual table. The CSV virtual table can be used anywhere an ordinary
+virtual table can be used. One can use the CSV virtual table inside subqueries,
+or <a href="lang_with.html">common table expressions</a> or add WHERE, GROUP BY, HAVING, ORDER BY,
+and LIMIT clauses as required.
+
+</p><h1 id="arguments"><span>2. </span>Arguments</h1>
+
+<p>
+The example above showed a single <b>filename='thefile.csv'</b> argument
+for the CSV virtual table. But other arguments are also possible.
+
+</p><ul>
+<li><p><b>filename=</b><i>FILENAME</i>
+</p><p>The <b>filename=</b> argument specifies an external file from which
+CSV content is read. Every CSV virtual table must have either a
+<b>filename=</b> argument or a <b>data=</b> argument and not both.
+
+</p></li><li><p><b>data=</b><i>TEXT</i>
+</p><p>The <b>data=</b> argument specifies that <i>TEXT</i> is the literal
+content of the CSV file.
+
+</p></li><li><p><b>schema=</b><i>SCHEMA</i>
+</p><p> The <b>schema=</b> argument specifies a <a href="lang_createtable.html">CREATE TABLE</a> statement that
+the CSV virtual table passes to the <a href="c3ref/declare_vtab.html">sqlite3_declare_vtab()</a> interface in
+order to define the names of the columns in the virtual table.
+
+</p></li><li><p><b>columns=</b><i>N</i>
+</p><p>The <b>columns=</b><i>N</i> argument specifies the number of columns
+in the CSV file.
+If the input data contains more columns than this,
+then the excess columns are ignored. If the input data contains fewer columns,
+then extra columns are filled with NULL.
+If the <b>columns=</b><i>N</i> argument is omitted, the first line of the
+CSV file is read to determine the number of columns.
+
+</p></li><li><p><b>header=</b><i>BOOLEAN</i><br>
+or just<br>
+<b>header</b>
+</p><p>If the <b>header</b> argument is true then the first row of the CSV file
+to be treated as a header rather than as data. The second line of the CSV
+file becomes the first row of content.
+If the <b>schema=</b> options is omitted, then the first line of the CSV
+file determines the names of the columns.
+</p></li></ul>
+
+<h1 id="column_names"><span>3. </span>Column Names</h1>
+
+<p>
+The column names of the virtual table are determined primarily by the
+<b>schema=</b> argument.
+If the <b>schema=</b> argument is omitted, but <b>header</b> is true, then
+the values found in the first line of the CSV file become the column names.
+If the <b>schema=</b> argument is omitted and <b>header</b> is false, then
+the columns are named "c0", "c1", "c2", and so forth.
+</p><p align="center"><small><i>This page last modified on <a href="https://sqlite.org/docsrc/honeypot" id="mtimelink" data-href="https://sqlite.org/docsrc/finfo/pages/csv.in?m=5f8e2137c13221b7b">2018-11-16 01:45:15</a> UTC </small></i></p>
+