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<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>2.4. Populating a Table With Rows</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="tutorial-table.html" title="2.3. Creating a New Table" /><link rel="next" href="tutorial-select.html" title="2.5. Querying a Table" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">2.4. Populating a Table With Rows</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="tutorial-table.html" title="2.3. Creating a New Table">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><th width="60%" align="center">Chapter 2. The <acronym class="acronym">SQL</acronym> Language</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="tutorial-select.html" title="2.5. Querying a Table">Next</a></td></tr></table><hr /></div><div class="sect1" id="TUTORIAL-POPULATE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">2.4. Populating a Table With Rows <a href="#TUTORIAL-POPULATE" class="id_link">#</a></h2></div></div></div><a id="id-1.4.4.5.2" class="indexterm"></a><p> The <code class="command">INSERT</code> statement is used to populate a table with rows: </p><pre class="programlisting"> INSERT INTO weather VALUES ('San Francisco', 46, 50, 0.25, '1994-11-27'); </pre><p> Note that all data types use rather obvious input formats. Constants that are not simple numeric values usually must be surrounded by single quotes (<code class="literal">'</code>), as in the example. The <code class="type">date</code> type is actually quite flexible in what it accepts, but for this tutorial we will stick to the unambiguous format shown here. </p><p> The <code class="type">point</code> type requires a coordinate pair as input, as shown here: </p><pre class="programlisting"> INSERT INTO cities VALUES ('San Francisco', '(-194.0, 53.0)'); </pre><p> </p><p> The syntax used so far requires you to remember the order of the columns. An alternative syntax allows you to list the columns explicitly: </p><pre class="programlisting"> INSERT INTO weather (city, temp_lo, temp_hi, prcp, date) VALUES ('San Francisco', 43, 57, 0.0, '1994-11-29'); </pre><p> You can list the columns in a different order if you wish or even omit some columns, e.g., if the precipitation is unknown: </p><pre class="programlisting"> INSERT INTO weather (date, city, temp_hi, temp_lo) VALUES ('1994-11-29', 'Hayward', 54, 37); </pre><p> Many developers consider explicitly listing the columns better style than relying on the order implicitly. </p><p> Please enter all the commands shown above so you have some data to work with in the following sections. </p><p> <a id="id-1.4.4.5.7.1" class="indexterm"></a> You could also have used <code class="command">COPY</code> to load large amounts of data from flat-text files. This is usually faster because the <code class="command">COPY</code> command is optimized for this application while allowing less flexibility than <code class="command">INSERT</code>. An example would be: </p><pre class="programlisting"> COPY weather FROM '/home/user/weather.txt'; </pre><p> where the file name for the source file must be available on the machine running the backend process, not the client, since the backend process reads the file directly. You can read more about the <code class="command">COPY</code> command in <a class="xref" href="sql-copy.html" title="COPY"><span class="refentrytitle">COPY</span></a>. </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="tutorial-table.html" title="2.3. Creating a New Table">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="tutorial-select.html" title="2.5. Querying a Table">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2.3. Creating a New Table </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 2.5. Querying a Table</td></tr></table></div></body></html>