CREATE OR REPLACE SPATIAL REFERENCE SYSTEMsridsrs_attribute... CREATE SPATIAL REFERENCE SYSTEM [IF NOT EXISTS]sridsrs_attribute...srs_attribute: { NAME 'srs_name' | DEFINITION 'definition' | ORGANIZATION 'org_name' IDENTIFIED BYorg_id| DESCRIPTION 'description' }srid,org_id:32-bit unsigned integer
This statement creates aspatial reference system(SRS) definition and stores it in the data dictionary. It requires theSUPER
privilege. The resulting data dictionary entry can be inspected using theINFORMATION_SCHEMA
ST_SPATIAL_REFERENCE_SYSTEMS
table.
SRID values must be unique, so if neitherOR REPLACE
norIF NOT EXISTS
is specified, an error occurs if an SRS definition with the givensrid
value already exists.
WithCREATE OR REPLACE
syntax, any existing SRS definition with the same SRID value is replaced, unless the SRID value is used by some column in an existing table. In that case, an error occurs. For example:
mysql> CREATE OR REPLACE SPATIAL REFERENCE SYSTEM 4326 ...; ERROR 3716 (SR005): Can't modify SRID 4326. There is at least one column depending on it.
To identify which column or columns use the SRID, use this query, replacing 4326 with the SRID of the definition you are trying to create:
SELECT * FROM INFORMATION_SCHEMA.ST_GEOMETRY_COLUMNS WHERE SRS_ID=4326;
WithCREATE ... IF NOT EXISTS
syntax, any existing SRS definition with the same SRID value causes the new definition to be ignored and a warning occurs.
SRID values must be in the range of 32-bit unsigned integers, with these restrictions:
SRID 0 is a valid SRID but cannot be used with
CREATE SPATIAL REFERENCE SYSTEM
.If the value is in a reserved SRID range, a warning occurs. Reserved ranges are [0, 32767] (reserved by EPSG), [60,000,000, 69,999,999] (reserved by EPSG), and [2,000,000,000, 2,147,483,647] (reserved by MySQL). EPSG stands for theEuropean Petroleum Survey Group.
Users should not create SRSs with SRIDs in the reserved ranges. Doing so runs the risk of the SRIDs conflicting with future SRS definitions distributed with MySQL, with the result that the new system-provided SRSs are not installed for MySQL upgrades or that the user-defined SRSs are overwritten.
Attributes for the statement must satisfy these conditions:
Attributes can be given in any order, but no attribute can be given more than once.
The
NAME
andDEFINITION
attributes are mandatory.The
NAME
srs_name
attribute value must be unique. The combination of theORGANIZATION
org_name
andorg_id
attribute values must be unique.The
NAME
srs_name
attribute value andORGANIZATION
org_name
attribute value cannot be empty or begin or end with whitespace.String values in attribute specifications cannot contain control characters, including newline.
The following table shows the maximum lengths for string attribute values.
Table 13.6 CREATE SPATIAL REFERENCE SYSTEM Attribute Lengths
Attribute Maximum Length (characters) NAME
80 DEFINITION
4096 ORGANIZATION
256 DESCRIPTION
2048
Here is an exampleCREATE SPATIAL REFERENCE SYSTEM
statement. TheDEFINITION
value is reformatted across multiple lines for readability. (For the statement to be legal, the value actually must be given on a single line.)
CREATE SPATIAL REFERENCE SYSTEM 4120 NAME 'Greek' ORGANIZATION 'EPSG' IDENTIFIED BY 4120 DEFINITION 'GEOGCS["Greek",DATUM["Greek",SPHEROID["Bessel 1841", 6377397.155,299.1528128,AUTHORITY["EPSG","7004"]], AUTHORITY["EPSG","6120"]],PRIMEM["Greenwich",0, AUTHORITY["EPSG","8901"]],UNIT["degree",0.017453292519943278, AUTHORITY["EPSG","9122"]],AXIS["Lat",NORTH],AXIS["Lon",EAST], AUTHORITY["EPSG","4120"]]';
The grammar for SRS definitions is based on the grammar defined inOpenGIS Implementation Specification: Coordinate Transformation Services, Revision 1.00, OGC 01-009, January 12, 2001, Section 7.2. This specification is available athttp://www.opengeospatial.org/standards/ct.
MySQL incorporates these changes to the specification:
Only the
production rule is implemented (that is, geographic and projected SRSs).There is an optional, nonstandard
clause for
. This makes it possible to recognize projection parameters by authority instead of name.The specification does not make
AXIS
clauses mandatory inGEOGCS
spatial reference system definitions. However, if there are noAXIS
clauses, MySQL cannot determine whether a definition has axes in latitude-longitude order or longitude-latitude order. MySQL enforces the nonstandard requirement that eachGEOGCS
definition must include twoAXIS
clauses. One must beNORTH
or南
, and the otherEAST
orWEST
. TheAXIS
clause order determines whether the definition has axes in latitude-longitude order or longitude-latitude order.SRS definitions may not contain newlines.
If an SRS definition specifies an authority code for the projection (which is recommended), an error occurs if the definition is missing mandatory parameters. In this case, the error message indicates what the problem is. The projection methods and mandatory parameters that MySQL supports are shown inTable 13.7, “Supported Spatial Reference System Projection Methods”andTable 13.8, “Spatial Reference System Projection Parameters”.
For additional information about writing SRS definitions for MySQL, seeGeographic Spatial Reference Systems in MySQL 8.0andProjected Spatial Reference Systems in MySQL 8.0
The following table shows the projection methods that MySQL supports. MySQL permits unknown projection methods but cannot check the defintion for mandatory paramters and cannot convert spatial data to or from an unknown projection. For detailed explanations of how each projection works, including formulas, seeEPSG Guidance Note 7-2.
Table 13.7 Supported Spatial Reference System Projection Methods
EPSG Code | Projection Name | Mandatory Parameters (EPSG Codes) |
---|---|---|
1024 | Popular Visualisation Pseudo Mercator | 8801, 8802, 8806, 8807 |
1027 | Lambert Azimuthal Equal Area (Spherical) | 8801, 8802, 8806, 8807 |
1028 | Equidistant Cylindrical | 8823, 8802, 8806, 8807 |
1029 | 等距圆柱(球) | 8823, 8802, 8806, 8807 |
1041 | Krovak (North Orientated) | 8811, 8833, 1036, 8818, 8819, 8806, 8807 |
1042 | Krovak Modified | 8811, 8833, 1036, 8818, 8819, 8806, 8807, 8617, 8618, 1026, 1027, 1028, 1029, 1030, 1031, 1032, 1033, 1034, 1035 |
1043 | Krovak Modified (North Orientated) | 8811, 8833, 1036, 8818, 8819, 8806, 8807, 8617, 8618, 1026, 1027, 1028, 1029, 1030, 1031, 1032, 1033, 1034, 1035 |
1051 | 兰伯特圆锥共形(2 sp密歇根州) | 8821, 8822, 8823, 8824, 8826, 8827, 1038 |
1052 | Colombia Urban | 8801, 8802, 8806, 8807, 1039 |
9801 | 兰伯特圆锥Conformal (1SP) | 8801, 8802, 8805, 8806, 8807 |
9802 | 兰伯特圆锥Conformal (2SP) | 8821, 8822, 8823, 8824, 8826, 8827 |
9803 | 兰伯特圆锥Conformal (2SP Belgium) | 8821, 8822, 8823, 8824, 8826, 8827 |
9804 | Mercator (variant A) | 8801, 8802, 8805, 8806, 8807 |
9805 | Mercator (variant B) | 8823, 8802, 8806, 8807 |
9806 | Cassini-Soldner | 8801, 8802, 8806, 8807 |
9807 | Transverse Mercator | 8801, 8802, 8805, 8806, 8807 |
9808 | Transverse Mercator (South Orientated) | 8801, 8802, 8805, 8806, 8807 |
9809 | Oblique Stereographic | 8801, 8802, 8805, 8806, 8807 |
9810 | Polar Stereographic (variant A) | 8801, 8802, 8805, 8806, 8807 |
9811 | New Zealand Map Grid | 8801, 8802, 8806, 8807 |
9812 | Hotine Oblique Mercator (variant A) | 8811, 8812, 8813, 8814, 8815, 8806, 8807 |
9813 | Laborde Oblique Mercator | 8811, 8812, 8813, 8815, 8806, 8807 |
9815 | Hotine Oblique Mercator (variant B) | 8811, 8812, 8813, 8814, 8815, 8816, 8817 |
9816 | Tunisia Mining Grid | 8821, 8822, 8826, 8827 |
9817 | 兰伯特圆锥Near-Conformal | 8801, 8802, 8805, 8806, 8807 |
9818 | American Polyconic | 8801, 8802, 8806, 8807 |
9819 | Krovak | 8811, 8833, 1036, 8818, 8819, 8806, 8807 |
9820 | Lambert Azimuthal Equal Area | 8801, 8802, 8806, 8807 |
9822 | Albers Equal Area | 8821, 8822, 8823, 8824, 8826, 8827 |
9824 | Transverse Mercator Zoned Grid System | 8801, 8830, 8831, 8805, 8806, 8807 |
9826 | 兰伯特圆锥Conformal (West Orientated) | 8801, 8802, 8805, 8806, 8807 |
9828 | Bonne (South Orientated) | 8801, 8802, 8806, 8807 |
9829 | Polar Stereographic (variant B) | 8832, 8833, 8806, 8807 |
9830 | Polar Stereographic (variant C) | 8832, 8833, 8826, 8827 |
9831 | Guam Projection | 8801, 8802, 8806, 8807 |
9832 | Modified Azimuthal Equidistant | 8801, 8802, 8806, 8807 |
9833 | Hyperbolic Cassini-Soldner | 8801, 8802, 8806, 8807 |
9834 | Lambert Cylindrical Equal Area (Spherical) | 8823, 8802, 8806, 8807 |
9835 | Lambert Cylindrical Equal Area | 8823, 8802, 8806, 8807 |
The following table shows the projection parameters that MySQL recognizes. Recognition occurs primarily by authority code. If there is no authority code, MySQL falls back to case-insensitive string matching on the parameter name. For details about each parameter, look it up by code in theEPSG Online Registry.
Table 13.8 Spatial Reference System Projection Parameters
EPSG Code | Fallback Name (Recognized by MySQL) | EPSG Name |
---|---|---|
1026 | c1 | C1 |
1027 | c2 | C2 |
1028 | c3 | C3 |
1029 | c4 | C4 |
1030 | c5 | C5 |
1031 | c6 | C6 |
1032 | c7 | C7 |
1033 | c8 | C8 |
1034 | c9 | C9 |
1035 | c10 | C10 |
1036 | azimuth | Co-latitude of cone axis |
1038 | ellipsoid_scale_factor | Ellipsoid scaling factor |
1039 | projection_plane_height_at_origin | Projection plane origin height |
8617 | evaluation_point_ordinate_1 | Ordinate 1 of evaluation point |
8618 | evaluation_point_ordinate_2 | Ordinate 2 of evaluation point |
8801 | latitude_of_origin | Latitude of natural origin |
8802 | central_meridian | Longitude of natural origin |
8805 | scale_factor | Scale factor at natural origin |
8806 | false_easting | False easting |
8807 | false_northing | False northing |
8811 | latitude_of_center | Latitude of projection centre |
8812 | longitude_of_center | Longitude of projection centre |
8813 | azimuth | Azimuth of initial line |
8814 | rectified_grid_angle | Angle from Rectified to Skew Grid |
8815 | scale_factor | Scale factor on initial line |
8816 | false_easting | Easting at projection centre |
8817 | false_northing | Northing at projection centre |
8818 | pseudo_standard_parallel_1 | Latitude of pseudo standard parallel |
8819 | scale_factor | Scale factor on pseudo standard parallel |
8821 | latitude_of_origin | Latitude of false origin |
8822 | central_meridian | 经度的起源 |
8823 | standard_parallel_1, standard_parallel1 | Latitude of 1st standard parallel |
8824 | standard_parallel_2, standard_parallel2 | Latitude of 2nd standard parallel |
8826 | false_easting | Easting at false origin |
8827 | false_northing | Northing at false origin |
8830 | initial_longitude | Initial longitude |
8831 | zone_width | Zone width |
8832 | standard_parallel | Latitude of standard parallel |
8833 | longitude_of_center | Longitude of origin |