ST_LineFromWKB
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## Name

ST_LineFromWKB — Makes a `LINESTRING` from WKB with the given SRID

## Synopsis

`geometry ST_LineFromWKB(`bytea WKB`)`;

`geometry ST_LineFromWKB(`bytea WKB, integer srid`)`;

## Description

The `ST_LineFromWKB` function, takes a well-known binary representation of geometry and a Spatial Reference System ID (`SRID`) and creates an instance of the appropriate geometry type - in this case, a `LINESTRING` geometry. This function plays the role of the Geometry Factory in SQL.

If an SRID is not specified, it defaults to 0. `NULL` is returned if the input `bytea` does not represent a `LINESTRING`.

OGC SPEC 3.2.6.2 - option SRID is from the conformance suite.

If you know all your geometries are `LINESTRING`s, its more efficient to just use ST_GeomFromWKB. This function just calls ST_GeomFromWKB and adds additional validation that it returns a linestring.

This method implements the OGC Simple Features Implementation Specification for SQL 1.1. s3.2.6.2

This method implements the SQL/MM specification. SQL-MM 3: 7.2.9

## Examples

    SELECT ST_LineFromWKB(ST_AsBinary(ST_GeomFromText('LINESTRING(1 2, 3 4)'))) AS aline,
    		ST_LineFromWKB(ST_AsBinary(ST_GeomFromText('POINT(1 2)'))) IS NULL AS null_return;
    aline                            | null_return
    ------------------------------------------------
    010200000002000000000000000000F ... | t

## See Also

ST_GeomFromWKB, ST_LinestringFromWKB

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