Unformatted text preview: Geometry Examples I In the SDO_ORDINATES array (explained in Section 2.2.5), specify the coordinates
of the end point for the orientation vector from the point, with values between 1
and 1. The orientation start point is assumed to be (0,0), and it is translated to the
location of the physical point to which it corresponds. Figure 2—7 illustrates an oriented point geometry at coordinates (12,14), with an
orientation vector of approximately 34 degrees (counterclockwise from the xaxis),
reﬂecting the orientation coordinates 03,02. (To have an orientation that more
precisely matches a specific angle, refer to the cotangent or tangent values in the tables
in a trigonometry textbook.) The orientation vector in this example goes from (0,0) to
(03,02) and extends onward. Assuming i=0.3 and j=0.2, the angle in radians can be
calculated as follows: angle in radians = arctan (j / i). The angle is then applied to the
physical point associated with the orientation vector. Figure 2—7 Oriented Point Geometry I ' 2
(12,14, 0.3.0.2) In the SDO_GEOMETRY definition of the geometry illustrated in Figure 2—7: I SDO_GTYPE : 2001. The 2 indicates two—dimensional, and the 1 indicates a single
point. I SDO_SRID = NULL.
I SDOJ’OINT = NULL. I SDO_ELEM_INFO = (1,1,1, 3,1,0). The ﬁnal 1,0 in 3,1,0 indicates that this is an
oriented point. I SDO_ORDINATES = (12,14, 03,02). The 12,14 identifies the physical coordinates
of the point; and the 0.3,0.2 identifies the x and y coordinates (assuming 12,14 as
the origin) of the end point of the orientation vector. The resulting orientation
vector slopes upward at about a 34degree angle. Example 2—10 shows a SQL statement that inserts the geometry illustrated in
Figure 2—7 into the database. Example 2—10 SOL Statement to Insert an Oriented Point Geometry INSERT INTO cola_markets VALUEsl
91, 222 Oracle Spatial User's Guide and Reference ...
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 Spring '09
 eckberg
 Databases

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