ST_MultiLineString function

The ST_MultiLineString function constructs a multilinestring from a given input.

The input can be given in one of the following formats:

A well-known text representation
A well-known binary representation
A shape representation
A representation in the geography markup language (GML)

An optional spatial reference system identifier can be specified to identify the spatial reference system that the resulting multilinestring is in.

If the well-known text representation, the well-known binary representation, the shape representation, or the GML representation is null, then null is returned.

Syntax

Parameters

wkt

A value of type CLOB(2G) that contains the well-known text representation of the resulting multilinestring.

wkb

A value of type BLOB(2G) that contains the well-known binary representation of the resulting multilinestring.

gml

A value of type CLOB(2G) that represents the resulting multilinestring using the geography markup language.

shape

A value of type BLOB(2G) that represents the shape representation of the resulting multilinestring.

srs_id

A value of type INTEGER that identifies the spatial reference system for the resulting multilinestring.

If the srs_id parameter is omitted, then the spatial reference system with the numeric identifier 0 (zero) is used.

If srs_id does not identify a spatial reference system listed in the catalog view DB2GSE.ST_SPATIAL_REFERENCE_SYSTEMS, then an exception condition is raised (SQLSTATE 38SU1).

Return type

db2gse.ST_MultiLineString

Example

In the following example, the lines of results have been reformatted for readability. The spacing in your results will vary according to your online display.

This example illustrates how ST_MultiLineString can be used to create and insert a multilinestring from its well-known text representation. The record that is inserted has ID = 1110, and the geometry is a multilinestring in spatial reference system 1. The multilinestring is in the well-known text representation of a multilinestring. The X and Y coordinates for this geometry are:

Line 1: (33, 2) (34, 3) (35, 6)
Line 2: (28, 4) (29, 5) (31, 8) (43, 12)
Line 3: (39, 3) (37, 4) (36, 7)


SET CURRENT FUNCTION PATH = CURRENT FUNCTION PATH, db2gse
CREATE TABLE sample_mlines (id INTEGER, 
                            geometry ST_MultiLineString)

INSERT INTO sample_mlines
  VALUES (1110,
          ST_MultiLineString ('multilinestring ( (33 2, 34 3, 35 6),
                                       (28 4, 29 5, 31 8, 43 12),
                                       (39 3, 37 4, 36 7) )', 1) )

The following SELECT statement returns the multilinestring that was recorded in the table:


SELECT id,
       CAST( ST_AsText( geometry ) AS VARCHAR(280) )
  MULTI_LINE_STRING
  FROM sample_mlines
  WHERE id = 1110

Results:


ID         MULTI_LINE_STRING
------- --------------------------------------------------------------------
   1110 MULTILINESTRING (( 33.00000000 2.00000000, 34.00000000 3.00000000,
              35.00000000 6.00000000),
                         ( 28.00000000 4.00000000, 29.00000000 5.00000000,
              31.00000000 8.0000000, 43.00000000 12.00000000),
                         ( 39.00000000 3.00000000, 37.00000000 4.00000000,
              36.00000000 7.00000000 ))