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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>2.3. Creating a New Table</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-concepts.html" title="2.2. Concepts" /><link rel="next" href="tutorial-populate.html" title="2.4. Populating a Table With Rows" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">2.3. Creating a New Table</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="tutorial-concepts.html" title="2.2. Concepts">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 15.7 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="tutorial-populate.html" title="2.4. Populating a Table With Rows">Next</a></td></tr></table><hr /></div><div class="sect1" id="TUTORIAL-TABLE"><div class="titlepage"><div><div><h2 class="title" style="clear: both">2.3. Creating a New Table</h2></div></div></div><a id="id-1.4.4.4.2" class="indexterm"></a><p>
    You  can  create  a  new  table by specifying the table
    name, along with all column names and their types:

</p><pre class="programlisting">
CREATE TABLE weather (
    city            varchar(80),
    temp_lo         int,           -- low temperature
    temp_hi         int,           -- high temperature
    prcp            real,          -- precipitation
    date            date
);
</pre><p>

    You can enter this into <code class="command">psql</code> with the line
    breaks.  <code class="command">psql</code> will recognize that the command
    is not terminated until the semicolon.
   </p><p>
    White space (i.e., spaces, tabs, and newlines) can be used freely
    in SQL commands.  That means you can type the command aligned
    differently than above, or even all on one line.  Two dashes
    (<span class="quote"><span class="quote"><code class="literal">--</code></span></span>) introduce comments.
    Whatever follows them is ignored up to the end of the line.  SQL
    is case insensitive about key words and identifiers, except
    when identifiers are double-quoted to preserve the case (not done
    above).
   </p><p>
    <code class="type">varchar(80)</code> specifies a data type that can store
    arbitrary character strings up to 80 characters in length.
    <code class="type">int</code> is the normal integer type.  <code class="type">real</code> is
    a type for storing single precision floating-point numbers.
    <code class="type">date</code> should be self-explanatory.  (Yes, the column of
    type <code class="type">date</code> is also named <code class="structfield">date</code>.
    This might be convenient or confusing — you choose.)
   </p><p>
    <span class="productname">PostgreSQL</span> supports the standard
    <acronym class="acronym">SQL</acronym> types <code class="type">int</code>,
    <code class="type">smallint</code>, <code class="type">real</code>, <code class="type">double
    precision</code>, <code class="type">char(<em class="replaceable"><code>N</code></em>)</code>,
    <code class="type">varchar(<em class="replaceable"><code>N</code></em>)</code>, <code class="type">date</code>,
    <code class="type">time</code>, <code class="type">timestamp</code>, and
    <code class="type">interval</code>, as well as other types of general utility
    and a rich set of geometric types.
    <span class="productname">PostgreSQL</span> can be customized with an
    arbitrary number of user-defined data types.  Consequently, type
    names are not key words in the syntax, except where required to
    support special cases in the <acronym class="acronym">SQL</acronym> standard.
   </p><p>
    The second example will store cities and their associated
    geographical location:
</p><pre class="programlisting">
CREATE TABLE cities (
    name            varchar(80),
    location        point
);
</pre><p>
    The <code class="type">point</code> type is an example of a
    <span class="productname">PostgreSQL</span>-specific data type.
   </p><p>
    <a id="id-1.4.4.4.8.1" class="indexterm"></a>

    Finally, it should be mentioned that if you don't need a table any
    longer or want to recreate it differently you can remove it using
    the following command:
</p><pre class="synopsis">
DROP TABLE <em class="replaceable"><code>tablename</code></em>;
</pre><p>
   </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="tutorial-concepts.html" title="2.2. Concepts">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-populate.html" title="2.4. Populating a Table With Rows">Next</a></td></tr><tr><td width="40%" align="left" valign="top">2.2. Concepts </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 15.7 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 2.4. Populating a Table With Rows</td></tr></table></div></body></html>