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  1. <?xml version="1.0" encoding="UTF-8" standalone="no"?>
  2. <!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 V1.79.1" /><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><div xmlns="http://www.w3.org/TR/xhtml1/transitional" 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 xmlns="http://www.w3.org/1999/xhtml" class="acronym">SQL</acronym> Language</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 12.4 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></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</h2></div></div></div><a id="id-1.4.4.5.2" class="indexterm"></a><p>
  3. The <code class="command">INSERT</code> statement is used to populate a table with
  4. rows:
  5. </p><pre class="programlisting">
  6. INSERT INTO weather VALUES ('San Francisco', 46, 50, 0.25, '1994-11-27');
  7. </pre><p>
  8. Note that all data types use rather obvious input formats.
  9. Constants that are not simple numeric values usually must be
  10. surrounded by single quotes (<code class="literal">'</code>), as in the example.
  11. The
  12. <code class="type">date</code> type is actually quite flexible in what it
  13. accepts, but for this tutorial we will stick to the unambiguous
  14. format shown here.
  15. </p><p>
  16. The <code class="type">point</code> type requires a coordinate pair as input,
  17. as shown here:
  18. </p><pre class="programlisting">
  19. INSERT INTO cities VALUES ('San Francisco', '(-194.0, 53.0)');
  20. </pre><p>
  21. </p><p>
  22. The syntax used so far requires you to remember the order of the
  23. columns. An alternative syntax allows you to list the columns
  24. explicitly:
  25. </p><pre class="programlisting">
  26. INSERT INTO weather (city, temp_lo, temp_hi, prcp, date)
  27. VALUES ('San Francisco', 43, 57, 0.0, '1994-11-29');
  28. </pre><p>
  29. You can list the columns in a different order if you wish or
  30. even omit some columns, e.g., if the precipitation is unknown:
  31. </p><pre class="programlisting">
  32. INSERT INTO weather (date, city, temp_hi, temp_lo)
  33. VALUES ('1994-11-29', 'Hayward', 54, 37);
  34. </pre><p>
  35. Many developers consider explicitly listing the columns better
  36. style than relying on the order implicitly.
  37. </p><p>
  38. Please enter all the commands shown above so you have some data to
  39. work with in the following sections.
  40. </p><p>
  41. <a id="id-1.4.4.5.7.1" class="indexterm"></a>
  42. You could also have used <code class="command">COPY</code> to load large
  43. amounts of data from flat-text files. This is usually faster
  44. because the <code class="command">COPY</code> command is optimized for this
  45. application while allowing less flexibility than
  46. <code class="command">INSERT</code>. An example would be:
  47. </p><pre class="programlisting">
  48. COPY weather FROM '/home/user/weather.txt';
  49. </pre><p>
  50. where the file name for the source file must be available on the
  51. machine running the backend process, not the client, since the backend process
  52. reads the file directly. You can read more about the
  53. <code class="command">COPY</code> command in <a class="xref" href="sql-copy.html" title="COPY"><span class="refentrytitle">COPY</span></a>.
  54. </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">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="tutorial-sql.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="tutorial-select.html">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">Home</a></td><td width="40%" align="right" valign="top"> 2.5. Querying a Table</td></tr></table></div></body></html>
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