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(mysql.info) populating-spatial-columns

Info Catalog (mysql.info) creating-spatial-columns (mysql.info) creating-a-spatially-enabled-mysql-database (mysql.info) fetching-spatial-data
 
 16.4.4 Populating Spatial Columns
 ---------------------------------
 
 After you have created spatial columns, you can populate them with
 spatial data.
 
 Values should be stored in internal geometry format, but you can
 convert them to that format from either Well-Known Text (WKT) or
 Well-Known Binary (WKB) format. The following examples demonstrate how
 to insert geometry values into a table by converting WKT values into
 internal geometry format:
 
    * Perform the conversion directly in the `INSERT' statement:
 
           INSERT INTO geom VALUES (GeomFromText('POINT(1 1)'));
 
           SET @g = 'POINT(1 1)';
           INSERT INTO geom VALUES (GeomFromText(@g));
 
    * Perform the conversion prior to the `INSERT':
 
           SET @g = GeomFromText('POINT(1 1)');
           INSERT INTO geom VALUES (@g);
 
 The following examples insert more complex geometries into the table:
 
      SET @g = 'LINESTRING(0 0,1 1,2 2)';
      INSERT INTO geom VALUES (GeomFromText(@g));
 
      SET @g = 'POLYGON((0 0,10 0,10 10,0 10,0 0),(5 5,7 5,7 7,5 7, 5 5))';
      INSERT INTO geom VALUES (GeomFromText(@g));
 
      SET @g =
      'GEOMETRYCOLLECTION(POINT(1 1),LINESTRING(0 0,1 1,2 2,3 3,4 4))';
      INSERT INTO geom VALUES (GeomFromText(@g));
 
 The preceding examples all use `GeomFromText()' to create geometry
 values. You can also use type-specific functions:
 
      SET @g = 'POINT(1 1)';
      INSERT INTO geom VALUES (PointFromText(@g));
 
      SET @g = 'LINESTRING(0 0,1 1,2 2)';
      INSERT INTO geom VALUES (LineStringFromText(@g));
 
      SET @g = 'POLYGON((0 0,10 0,10 10,0 10,0 0),(5 5,7 5,7 7,5 7, 5 5))';
      INSERT INTO geom VALUES (PolygonFromText(@g));
 
      SET @g =
      'GEOMETRYCOLLECTION(POINT(1 1),LINESTRING(0 0,1 1,2 2,3 3,4 4))';
      INSERT INTO geom VALUES (GeomCollFromText(@g));
 
 Note that if a client application program wants to use WKB
 representations of geometry values, it is responsible for sending
 correctly formed WKB in queries to the server. However, there are
 several ways of satisfying this requirement. For example:
 
    * Inserting a `POINT(1 1)' value with hex literal syntax:
 
           mysql> INSERT INTO geom VALUES
               -> (GeomFromWKB(0x0101000000000000000000F03F000000000000F03F));
 
    * An ODBC application can send a WKB representation, binding it to a
      placeholder using an argument of `BLOB' type:
 
           INSERT INTO geom VALUES (GeomFromWKB(?))
 
      Other programming interfaces may support a similar placeholder
      mechanism.
 
    * In a C program, you can escape a binary value using
      `mysql_real_escape_string()' and include the result in a query
      string that is sent to the server. See 
      mysql-real-escape-string.
 
Info Catalog (mysql.info) creating-spatial-columns (mysql.info) creating-a-spatially-enabled-mysql-database (mysql.info) fetching-spatial-data
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