diff options
Diffstat (limited to 'doc/src/sgml/html/tutorial-accessdb.html')
| -rw-r--r-- | doc/src/sgml/html/tutorial-accessdb.html | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/doc/src/sgml/html/tutorial-accessdb.html b/doc/src/sgml/html/tutorial-accessdb.html new file mode 100644 index 0000000..fa7685d --- /dev/null +++ b/doc/src/sgml/html/tutorial-accessdb.html @@ -0,0 +1,103 @@ +<?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>1.4. Accessing a Database</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-createdb.html" title="1.3. Creating a Database" /><link rel="next" href="tutorial-sql.html" title="Chapter 2. The SQL Language" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">1.4. Accessing a Database</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="tutorial-createdb.html" title="1.3. Creating a Database">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="tutorial-start.html" title="Chapter 1. Getting Started">Up</a></td><th width="60%" align="center">Chapter 1. Getting Started</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Next</a></td></tr></table><hr /></div><div class="sect1" id="TUTORIAL-ACCESSDB"><div class="titlepage"><div><div><h2 class="title" style="clear: both">1.4. Accessing a Database <a href="#TUTORIAL-ACCESSDB" class="id_link">#</a></h2></div></div></div><a id="id-1.4.3.5.2" class="indexterm"></a><p> + Once you have created a database, you can access it by: + + </p><div class="itemizedlist"><ul class="itemizedlist compact" style="list-style-type: bullet; "><li class="listitem" style="list-style-type: disc"><p> + Running the <span class="productname">PostgreSQL</span> interactive + terminal program, called <span class="application"><em class="firstterm">psql</em></span>, which allows you + to interactively enter, edit, and execute + <acronym class="acronym">SQL</acronym> commands. + </p></li><li class="listitem" style="list-style-type: disc"><p> + Using an existing graphical frontend tool like + <span class="application">pgAdmin</span> or an office suite with + <acronym class="acronym">ODBC</acronym> or <acronym class="acronym">JDBC</acronym> support to create and manipulate a + database. These possibilities are not covered in this + tutorial. + </p></li><li class="listitem" style="list-style-type: disc"><p> + Writing a custom application, using one of the several + available language bindings. These possibilities are discussed + further in <a class="xref" href="client-interfaces.html" title="Part IV. Client Interfaces">Part IV</a>. + </p></li></ul></div><p> + + You probably want to start up <code class="command">psql</code> to try + the examples in this tutorial. It can be activated for the + <code class="literal">mydb</code> database by typing the command: +</p><pre class="screen"> +<code class="prompt">$</code> <strong class="userinput"><code>psql mydb</code></strong> +</pre><p> + If you do not supply the database name then it will default to your + user account name. You already discovered this scheme in the + previous section using <code class="command">createdb</code>. + </p><p> + In <code class="command">psql</code>, you will be greeted with the following + message: +</p><pre class="screen"> +psql (16.2) +Type "help" for help. + +mydb=> +</pre><p> + <a id="id-1.4.3.5.4.3" class="indexterm"></a> + The last line could also be: +</p><pre class="screen"> +mydb=# +</pre><p> + That would mean you are a database superuser, which is most likely + the case if you installed the <span class="productname">PostgreSQL</span> instance + yourself. Being a superuser means that you are not subject to + access controls. For the purposes of this tutorial that is not + important. + </p><p> + If you encounter problems starting <code class="command">psql</code> + then go back to the previous section. The diagnostics of + <code class="command">createdb</code> and <code class="command">psql</code> are + similar, and if the former worked the latter should work as well. + </p><p> + The last line printed out by <code class="command">psql</code> is the + prompt, and it indicates that <code class="command">psql</code> is listening + to you and that you can type <acronym class="acronym">SQL</acronym> queries into a + work space maintained by <code class="command">psql</code>. Try out these + commands: + <a id="id-1.4.3.5.6.5" class="indexterm"></a> +</p><pre class="screen"> +<code class="prompt">mydb=></code> <strong class="userinput"><code>SELECT version();</code></strong> + version +------------------------------------------------------------------------------------------ + PostgreSQL 16.2 on x86_64-pc-linux-gnu, compiled by gcc (Debian 4.9.2-10) 4.9.2, 64-bit +(1 row) + +<code class="prompt">mydb=></code> <strong class="userinput"><code>SELECT current_date;</code></strong> + date +------------ + 2016-01-07 +(1 row) + +<code class="prompt">mydb=></code> <strong class="userinput"><code>SELECT 2 + 2;</code></strong> + ?column? +---------- + 4 +(1 row) +</pre><p> + </p><p> + The <code class="command">psql</code> program has a number of internal + commands that are not SQL commands. They begin with the backslash + character, <span class="quote">“<span class="quote"><code class="literal">\</code></span>”</span>. + For example, + you can get help on the syntax of various + <span class="productname">PostgreSQL</span> <acronym class="acronym">SQL</acronym> + commands by typing: +</p><pre class="screen"> +<code class="prompt">mydb=></code> <strong class="userinput"><code>\h</code></strong> +</pre><p> + </p><p> + To get out of <code class="command">psql</code>, type: +</p><pre class="screen"> +<code class="prompt">mydb=></code> <strong class="userinput"><code>\q</code></strong> +</pre><p> + and <code class="command">psql</code> will quit and return you to your + command shell. (For more internal commands, type + <code class="literal">\?</code> at the <code class="command">psql</code> prompt.) The + full capabilities of <code class="command">psql</code> are documented in + <a class="xref" href="app-psql.html" title="psql"><span class="refentrytitle"><span class="application">psql</span></span></a>. In this tutorial we will not use these + features explicitly, but you can use them yourself when it is helpful. + </p></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="tutorial-createdb.html" title="1.3. Creating a Database">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="tutorial-start.html" title="Chapter 1. Getting Started">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="tutorial-sql.html" title="Chapter 2. The SQL Language">Next</a></td></tr><tr><td width="40%" align="left" valign="top">1.3. Creating a Database </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.2 Documentation">Home</a></td><td width="40%" align="right" valign="top"> Chapter 2. The <acronym class="acronym">SQL</acronym> Language</td></tr></table></div></body></html>
\ No newline at end of file |