Categories:

Geospatial functions, Conversion functions

TRY_TO_GEOMETRY¶

Parses an input and returns a value of type GEOMETRY.

This function is identical to TO_GEOMETRY except that it returns NULL when TO_GEOMETRY would return an error.

See also:

TO_GEOMETRY

Syntax¶

Use one of the following:

TRY_TO_GEOMETRY( <varchar_expression> [ , <srid> ] [ , <allow_invalid> ] )

TRY_TO_GEOMETRY( <binary_expression> [ , <srid> ] [ , <allow_invalid> ] )

TRY_TO_GEOMETRY( <variant_expression> [ , <srid> ] [ , <allow_invalid> ] )
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Arguments¶

Required:

varchar_expression

The argument must be a string expression that represents a valid geometric object in one of the following formats:

  • WKT (well-known text).

  • WKB (well-known binary) in hexadecimal format (without a leading 0x).

  • EWKT (extended well-known text).

  • EWKB (extended well-known binary) in hexadecimal format (without a leading 0x).

  • GeoJSON.

binary_expression

The argument must be a binary expression in WKB or EWKB format.

variant_expression

The argument must be an OBJECT in GeoJSON format.

Optional:

srid

The integer value of the SRID to use.

allow_invalid

If TRUE, specifies that the function should return a GEOGRAPHY or GEOMETRY object, even when the input shape is invalid and cannot be repaired. For details, refer to Specifying how invalid geospatial shapes are handled.

Returns¶

The function returns a value of type GEOMETRY.

Usage notes¶

  • Returns NULL if the input cannot be parsed as the appropriate supported format (WKT, WKB, EWKT, EWKB, GeoJSON).

  • For GeoJSON, WKT, and WKB input, if the srid argument is not specified, the resulting GEOMETRY object has the SRID set to 0.

Examples¶

This shows a simple use of the TRY_TO_GEOMETRY function with VARCHAR data:

select try_to_geometry('INVALID INPUT');
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+--------------------------------------+
| try_to_geometry('INVALID INPUT')     |
|--------------------------------------|
| NULL                                 |
+--------------------------------------+
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