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   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>8.8. Geometric Types</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="datatype-enum.html" title="8.7. Enumerated Types" /><link rel="next" href="datatype-net-types.html" title="8.9. Network Address Types" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">8.8. Geometric Types</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="datatype-enum.html" title="8.7. Enumerated Types">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="datatype.html" title="Chapter 8. Data Types">Up</a></td><th width="60%" align="center">Chapter 8. Data Types</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="datatype-net-types.html" title="8.9. Network Address Types">Next</a></td></tr></table><hr /></div><div class="sect1" id="DATATYPE-GEOMETRIC"><div class="titlepage"><div><div><h2 class="title" style="clear: both">8.8. Geometric Types <a href="#DATATYPE-GEOMETRIC" class="id_link">#</a></h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-GEOMETRIC-POINTS">8.8.1. Points</a></span></dt><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-LINE">8.8.2. Lines</a></span></dt><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-LSEG">8.8.3. Line Segments</a></span></dt><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-GEOMETRIC-BOXES">8.8.4. Boxes</a></span></dt><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-GEOMETRIC-PATHS">8.8.5. Paths</a></span></dt><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-POLYGON">8.8.6. Polygons</a></span></dt><dt><span class="sect2"><a href="datatype-geometric.html#DATATYPE-CIRCLE">8.8.7. Circles</a></span></dt></dl></div><p>
   3     Geometric data types represent two-dimensional spatial
   4     objects. <a class="xref" href="datatype-geometric.html#DATATYPE-GEO-TABLE" title="Table 8.20. Geometric Types">Table 8.20</a> shows the geometric
   5     types available in <span class="productname">PostgreSQL</span>.
   6    </p><div class="table" id="DATATYPE-GEO-TABLE"><p class="title"><strong>Table 8.20. Geometric Types</strong></p><div class="table-contents"><table class="table" summary="Geometric Types" border="1"><colgroup><col class="col1" /><col class="col2" /><col class="col3" /><col class="col4" /></colgroup><thead><tr><th>Name</th><th>Storage Size</th><th>Description</th><th>Representation</th></tr></thead><tbody><tr><td><code class="type">point</code></td><td>16 bytes</td><td>Point on a plane</td><td>(x,y)</td></tr><tr><td><code class="type">line</code></td><td>24 bytes</td><td>Infinite line</td><td>{A,B,C}</td></tr><tr><td><code class="type">lseg</code></td><td>32 bytes</td><td>Finite line segment</td><td>[(x1,y1),(x2,y2)]</td></tr><tr><td><code class="type">box</code></td><td>32 bytes</td><td>Rectangular box</td><td>(x1,y1),(x2,y2)</td></tr><tr><td><code class="type">path</code></td><td>16+16n bytes</td><td>Closed path (similar to polygon)</td><td>((x1,y1),...)</td></tr><tr><td><code class="type">path</code></td><td>16+16n bytes</td><td>Open path</td><td>[(x1,y1),...]</td></tr><tr><td><code class="type">polygon</code></td><td>40+16n bytes</td><td>Polygon (similar to closed path)</td><td>((x1,y1),...)</td></tr><tr><td><code class="type">circle</code></td><td>24 bytes</td><td>Circle</td><td>&lt;(x,y),r&gt; (center point and radius)</td></tr></tbody></table></div></div><br class="table-break" /><p>
   7     In all these types, the individual coordinates are stored as
   8     <code class="type">double precision</code> (<code class="type">float8</code>) numbers.
   9    </p><p>
  10     A rich set of functions and operators is available to perform various geometric
  11     operations such as scaling, translation, rotation, and determining
  12     intersections.  They are explained in <a class="xref" href="functions-geometry.html" title="9.11. Geometric Functions and Operators">Section 9.11</a>.
  13    </p><div class="sect2" id="DATATYPE-GEOMETRIC-POINTS"><div class="titlepage"><div><div><h3 class="title">8.8.1. Points <a href="#DATATYPE-GEOMETRIC-POINTS" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.6.2" class="indexterm"></a><p>
  14      Points are the fundamental two-dimensional building block for geometric
  15      types.  Values of type <code class="type">point</code> are specified using either of
  16      the following syntaxes:
  17
  18 </p><pre class="synopsis">
  19 ( <em class="replaceable"><code>x</code></em> , <em class="replaceable"><code>y</code></em> )
  20   <em class="replaceable"><code>x</code></em> , <em class="replaceable"><code>y</code></em>
  21 </pre><p>
  22
  23      where <em class="replaceable"><code>x</code></em> and <em class="replaceable"><code>y</code></em> are the respective
  24      coordinates, as floating-point numbers.
  25     </p><p>
  26      Points are output using the first syntax.
  27     </p></div><div class="sect2" id="DATATYPE-LINE"><div class="titlepage"><div><div><h3 class="title">8.8.2. Lines <a href="#DATATYPE-LINE" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.7.2" class="indexterm"></a><p>
  28      Lines are represented by the linear
  29      equation <em class="replaceable"><code>A</code></em>x + <em class="replaceable"><code>B</code></em>y + <em class="replaceable"><code>C</code></em> = 0,
  30      where <em class="replaceable"><code>A</code></em> and <em class="replaceable"><code>B</code></em> are not both zero.  Values
  31      of type <code class="type">line</code> are input and output in the following form:
  32 </p><pre class="synopsis">
  33 { <em class="replaceable"><code>A</code></em>, <em class="replaceable"><code>B</code></em>, <em class="replaceable"><code>C</code></em> }
  34 </pre><p>
  35
  36      Alternatively, any of the following forms can be used for input:
  37
  38 </p><pre class="synopsis">
  39 [ ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> ) ]
  40 ( ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> ) )
  41   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> )
  42     <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   ,   <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em>
  43 </pre><p>
  44
  45      where
  46      <code class="literal">(<em class="replaceable"><code>x1</code></em>,<em class="replaceable"><code>y1</code></em>)</code>
  47      and
  48      <code class="literal">(<em class="replaceable"><code>x2</code></em>,<em class="replaceable"><code>y2</code></em>)</code>
  49      are two different points on the line.
  50     </p></div><div class="sect2" id="DATATYPE-LSEG"><div class="titlepage"><div><div><h3 class="title">8.8.3. Line Segments <a href="#DATATYPE-LSEG" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.8.2" class="indexterm"></a><a id="id-1.5.7.16.8.3" class="indexterm"></a><p>
  51      Line segments are represented by pairs of points that are the endpoints
  52      of the segment.  Values of type <code class="type">lseg</code> are specified using any
  53      of the following syntaxes:
  54
  55 </p><pre class="synopsis">
  56 [ ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> ) ]
  57 ( ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> ) )
  58   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> )
  59     <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   ,   <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em>
  60 </pre><p>
  61
  62      where
  63      <code class="literal">(<em class="replaceable"><code>x1</code></em>,<em class="replaceable"><code>y1</code></em>)</code>
  64      and
  65      <code class="literal">(<em class="replaceable"><code>x2</code></em>,<em class="replaceable"><code>y2</code></em>)</code>
  66      are the end points of the line segment.
  67     </p><p>
  68      Line segments are output using the first syntax.
  69     </p></div><div class="sect2" id="DATATYPE-GEOMETRIC-BOXES"><div class="titlepage"><div><div><h3 class="title">8.8.4. Boxes <a href="#DATATYPE-GEOMETRIC-BOXES" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.9.2" class="indexterm"></a><a id="id-1.5.7.16.9.3" class="indexterm"></a><p>
  70      Boxes are represented by pairs of points that are opposite
  71      corners of the box.
  72      Values of type <code class="type">box</code> are specified using any of the following
  73      syntaxes:
  74
  75 </p><pre class="synopsis">
  76 ( ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> ) )
  77   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ( <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em> )
  78     <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   ,   <em class="replaceable"><code>x2</code></em> , <em class="replaceable"><code>y2</code></em>
  79 </pre><p>
  80
  81      where
  82      <code class="literal">(<em class="replaceable"><code>x1</code></em>,<em class="replaceable"><code>y1</code></em>)</code>
  83      and
  84      <code class="literal">(<em class="replaceable"><code>x2</code></em>,<em class="replaceable"><code>y2</code></em>)</code>
  85      are any two opposite corners of the box.
  86     </p><p>
  87      Boxes are output using the second syntax.
  88     </p><p>
  89      Any two opposite corners can be supplied on input, but the values
  90      will be reordered as needed to store the
  91      upper right and lower left corners, in that order.
  92     </p></div><div class="sect2" id="DATATYPE-GEOMETRIC-PATHS"><div class="titlepage"><div><div><h3 class="title">8.8.5. Paths <a href="#DATATYPE-GEOMETRIC-PATHS" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.10.2" class="indexterm"></a><p>
  93      Paths are represented by lists of connected points. Paths can be
  94      <em class="firstterm">open</em>, where
  95      the first and last points in the list are considered not connected, or
  96      <em class="firstterm">closed</em>,
  97      where the first and last points are considered connected.
  98     </p><p>
  99      Values of type <code class="type">path</code> are specified using any of the following
 100      syntaxes:
 101
 102 </p><pre class="synopsis">
 103 [ ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ... , ( <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> ) ]
 104 ( ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ... , ( <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> ) )
 105   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ... , ( <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> )
 106   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   , ... ,   <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> )
 107     <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   , ... ,   <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em>
 108 </pre><p>
 109
 110      where the points are the end points of the line segments
 111      comprising the path.  Square brackets (<code class="literal">[]</code>) indicate
 112      an open path, while parentheses (<code class="literal">()</code>) indicate a
 113      closed path.  When the outermost parentheses are omitted, as
 114      in the third through fifth syntaxes, a closed path is assumed.
 115     </p><p>
 116      Paths are output using the first or second syntax, as appropriate.
 117     </p></div><div class="sect2" id="DATATYPE-POLYGON"><div class="titlepage"><div><div><h3 class="title">8.8.6. Polygons <a href="#DATATYPE-POLYGON" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.11.2" class="indexterm"></a><p>
 118      Polygons are represented by lists of points (the vertices of the
 119      polygon). Polygons are very similar to closed paths; the essential
 120      semantic difference is that a polygon is considered to include the
 121      area within it, while a path is not.
 122     </p><p>
 123      An important implementation difference between polygons and
 124      paths is that the stored representation of a polygon includes its
 125      smallest bounding box.  This speeds up certain search operations,
 126      although computing the bounding box adds overhead while constructing
 127      new polygons.
 128     </p><p>
 129      Values of type <code class="type">polygon</code> are specified using any of the
 130      following syntaxes:
 131
 132 </p><pre class="synopsis">
 133 ( ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ... , ( <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> ) )
 134   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em> ) , ... , ( <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> )
 135   ( <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   , ... ,   <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em> )
 136     <em class="replaceable"><code>x1</code></em> , <em class="replaceable"><code>y1</code></em>   , ... ,   <em class="replaceable"><code>xn</code></em> , <em class="replaceable"><code>yn</code></em>
 137 </pre><p>
 138
 139      where the points are the end points of the line segments
 140      comprising the boundary of the polygon.
 141     </p><p>
 142      Polygons are output using the first syntax.
 143     </p></div><div class="sect2" id="DATATYPE-CIRCLE"><div class="titlepage"><div><div><h3 class="title">8.8.7. Circles <a href="#DATATYPE-CIRCLE" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.16.12.2" class="indexterm"></a><p>
 144      Circles are represented by a center point and radius.
 145      Values of type <code class="type">circle</code> are specified using any of the
 146      following syntaxes:
 147
 148 </p><pre class="synopsis">
 149 &lt; ( <em class="replaceable"><code>x</code></em> , <em class="replaceable"><code>y</code></em> ) , <em class="replaceable"><code>r</code></em> &gt;
 150 ( ( <em class="replaceable"><code>x</code></em> , <em class="replaceable"><code>y</code></em> ) , <em class="replaceable"><code>r</code></em> )
 151   ( <em class="replaceable"><code>x</code></em> , <em class="replaceable"><code>y</code></em> ) , <em class="replaceable"><code>r</code></em>
 152     <em class="replaceable"><code>x</code></em> , <em class="replaceable"><code>y</code></em>   , <em class="replaceable"><code>r</code></em>
 153 </pre><p>
 154
 155      where
 156      <code class="literal">(<em class="replaceable"><code>x</code></em>,<em class="replaceable"><code>y</code></em>)</code>
 157      is the center point and <em class="replaceable"><code>r</code></em> is the radius of the
 158      circle.
 159     </p><p>
 160      Circles are output using the first syntax.
 161     </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="datatype-enum.html" title="8.7. Enumerated Types">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="datatype.html" title="Chapter 8. Data Types">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="datatype-net-types.html" title="8.9. Network Address Types">Next</a></td></tr><tr><td width="40%" align="left" valign="top">8.7. Enumerated Types </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="40%" align="right" valign="top"> 8.9. Network Address Types</td></tr></table></div></body></html>