Postgis Qgis Gr 2.0

PostgreSQL/PostGIS QuantumGIS

/

C reative Commons Attribution-NonCommercial-ShareAlike 3.0 -

/

1.0 22/06/2009 .

2.0 12/11/2009 . :

:

5.1.1.1 5.1.1.3 5.1.5 5.1.6 5.3.2

: 1. / 2. / .

: . SQL.

, / . :

2

1. ................................................................................................................................52. : ..................................................63. ......................................................................................8

3.1 PostgreSQL..............................................8 3.2 PostGIS.............................................................9 3.3 QuantumGIS ....................................................................................10

4. ..............................................................................................11 4.1 PostgreSQL/PostGIS.............................................................................................11 4.2 QuantumGIS...........................................................22

5. ...............................................................................................................265.1. .......................................................26

5.1.1 ...............................................265.1.1.1 (template) ..............265.1.1.2 (template) ..........315.1.1.3 ....................................................................32

5.1.2 ..............................................................................................335.1.3 SQL.............................345.1.4 *.shp.................................................................42

5.1.4.1 command line ........................................................435.1.4.2 QuantumGIS:......................465.1.4.3 QuantumGIS........................................................515.1.4.4 *.shp .........................53

5.1.5 ..................................................555.1.6 ......................................................................56

5.2 ................................................................................575.2.1 SQL ......................585.2.2 QuantumGIS......................................605.2.3 ..................................................................................................62

5.2.3.1 WITHIN CONTAINS................................................................625.2.3.2 DISTANCE.....................................................................................665.2.3.3 INTERSECTS................................................................................675.2.3.4 TOUCHES.....................................................................................695.2.3.5 AREA.............................................................................................715.2.3.6 ENVELOPE...................................................................................715.2.3.7 LENGTH .......................................................................................725.2.3.8 NPOINTS ......................................................................................72

5.3 ...................................735.3.1 QuantumGIS .......................................................................................73

5.3.1.1 .......................................................................................735.3.1.2 ..........................................................................................755.3.1.3 .......................................................................................755.3.1.4 ............................................................................................75

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5.3.1.5 ...........................................................................................755.3.1.6 .............................................................................................765.3.1.7 .................................................................76

5.3.2 UDIG...................................................................................................766. ....................................................................................................85

6.1 PL/pgSQL................................................................................85 6.2 PL/pgSQL....................................................86

6.2.1 ...............................................................................................................876.2.2 ...........................................................................................................90

7. ..................................................................................................................................928. ....................................................................................................................................93

4

1.

, . , ( ) . (). PostgreSQL PostGIS. , QuantumGIS, . , .

. . . PostgreSQL, PostGIS, QuantumGIS . , . PL/pgSQL PostgreSQL. (, ) PL/pgSQL.

: http :// www . ellak . gr / workshop _ postgis . zip . command line, SQL PL/pgSQL workshop.txt shapefiles (*.shp) SHP.

5

2. : .

, ( ) ( : , , , , .. - : , .) , . real estate, , , , , , , , , , .. ( GIS Geographical Information Systems).

, , , . (Desktop GIS) ( - Spatial Databases, Geodatabases).

, , . , , , , , , , .. , .

, , . . . SQL (Structured Query Language) .

, , .

6

. . , , . .

PostgreSQL/PostGIS QuantumGIS.

7

3.

3.1 PostgreSQL

PostgreSQL - (object-relational database management system - ORDBMS). , . PostgreSQL , (B+-tree, hash, GiST GiN), , , . , , , , , ..

PostgreSQL SQL . SQL . :

PL/pgSQL PostgreSQL PL/SQL Oracle

(scripting languages) PL/Lua, PL/LOLCODE, PL/Perl, plPHP, PL/Python, PL/Ruby, PL/sh, PL/Tcl, PL/Scheme, PL/Java, PL/R

C C++.

PostgreSQL R-. R- . . .

PostgreSQL (add-ons) .

8

PostGIS.

3.2 PostGIS

PostGIS OGC SQL. PostGIS :

:

o (points)o (linestrings)o (polygons) o (multipoints)o (multilinestrings)o - (multipolygons)

(Geometrycollections).

(spatial predicates) 3x3 Egenhofer.

area, distance, length, perimeter, union, difference, symmetric difference buffers.

R- (GIST).

PostGIS . (RAM) .

3.3 QuantumGIS

To QuantumGIS ( QGIS) , . Gary Sherman 2002 Open Source Geospatial Foundation. . QuantumGIS C++ Qt. C++ Python. 14 / .

QuantumGIS Linux, Unix, Windows Macintosh. PostGIS GRASS. . .

9

2002 PostgreSQL/PostGIS. shapefiles format. , raster , (. buffer) . , MapServer WMS WFS Open Geospatial Consortium. .

10

4.

4.1 PostgreSQL/PostGIS

PostgreSQL http :// www . postgresql . org / download / . . (beta). 8.3.7.1. (http :// wwwmaster . postgresql . org / redir /57/ h / binary / v 8.3.7/ win 32/ postgresql -8.3.7-1. zip ) postgresql-8.3.msi. :

1. start:

2. Next

11

3. next

4. Entire Feature will be installed on local hard drive PL/Java Development National language support. , .

12

5. . Service Name Account Name Account Domain . . . .

6. yes

13

7. Accept conections on all addresses, not just localhost. . . Encoding (Server) Encoding (Client) 'ISO_8859_7' 'UTF8'. . 5.

14

8. pg_hba.conf. .

15

9. PL/pgSQL.

10. . B-Tree GiST Dblink Integer Aggregator L-Tree PGStatTuple ModDateTime TableFunctions .

16

11. Next .

12. Finish Launch Stack Builder at exit.

17

13. Stack Builder PostgreSQL Database Server 8.3 on Port 5432 Next

14. PostGIS. http :// postgis . refractions . net / (stable) (beta) .

18

15. .

16. .

19

17. Create spatial database ( PostGIS )

18. . .

19. (username) (password),

20

7, .

20. PostgreSQL PostGIS .

21

4.2 QuantumGIS

. http :// www . qgis . org / en / download / binaries . html . . (standalone installer offline instaler) (online installer). . 1.02 windows (http :// download . osgeo . org / qgis / win 32/ QGIS - 1.0.2-0- Setup . exe ) .

QGIS-1.0.2-0-Setup.exe . :

1. 'Next'

2. 'I agree'

22

3. ( ) 'Next'

23

( , , ) . 360mb . 'Install'.

QuantumGIS . .

24

5.

5.1.

5.1.1

5.1.1.1 (template)

Start, Programs, PostgreSQL 8.3, pgAdmin III.

: PostGreSQL . (service). (client). pgAdminn III . . , pgAdminn III.

pgAdmin III . Servers (1) PostgreSQL Database Server 8.3 (localhost 5432). connect. postgres 7 (: 4.1 PostgreSQL/PostGIS).

25

+ PostgreSQL Database Server 8.3 (localhost 5432) . databases.

, postgres postgis. Databases (2) New Database.

26

. PostGIS. : PostGIS. :

:

, Databases ()

.

SQL : postgres Tools, Query tool. SQL . SQL:

CREATE DATABASE template_postgisWITH ENCODING='UTF8'OWNER = postgresTEMPLATE= postgisTABLESPACE = pg_default;

Query, Execute F5.

28

.

CREATE DATABASE thessalonikiWITH ENCODING='UTF8'OWNER = postgresTEMPLATE= template_postgisTABLESPACE = pg_default;

:Query returned successfully with no result in ....... ms

pgAdmin III. Databases (3) .

:

29

, thessaloniki , Tools, Query tool. SQL.

5.1.1.2 (template) (.. ), PostGIS.

pgAdmin III ( , Template ) SQL:

CREATE DATABASE my_dbWITHENCODING='UTF8'OWNER = postgresTABLESPACE = pg_default;

PostGIS.

:

. Databases object browser Refresh. my_db . my_db pgAdmin Tools, Query tool. . :

CREATE TABLE my_table(id INTEGER PRIMARY KEY,name VARCHAR(60));SELECT AddGeometryColumn('public','my_table','the_geom',4121,'LINESTRING',2);

PostGIS :

30

ERROR: function addgeometrycolumn("unknown", "unknown", "unknown", integer, "unknown", integer) does not existSQL state: 42883Hint: No function matches the given name and argument types. You may need to add explicit type casts.Character: 79

PostGIS, .

Databases object browser Refresh, my_db . my_db pgAdmin Tools, Query tool. File, open :

C:\Program Files\PostgreSQL\8.2\share\contrib\lwpostgis.sql

Query Execute.

:

C:\Program Files\PostgreSQL\8.2\share\contrib\spatial_ref_sys.sql

, my_db PostGIS.

5.1.1.3

:. pgAdminIIIB. Object browser PostgreSQL Database Server 8.2 (Localhost:5432) Connect.

31

PostgreSQL Database Server 8.2 (Localhost:5432) Databases. , Tools, Query tool. .

5.1.2

. , , , .. , ' public. SQL ( health_services):

CREATE SCHEMA health_servicesAUTHORIZATION postgres;GRANT ALL ON SCHEMA health_services TO postgres;GRANT ALL ON SCHEMA health_services TO public;

execute.

, , public health_services.

32

pgAdminIII New Object, New Schema.

5.1.3 SQL

. . (.. , , ). ( ) . :

SQL

*.shp shp2pgsql

*.shp QuantumGIS

SQL. . . :

()

. road_net. execute:

33

CREATE TABLE health_services.road_net(id INTEGER PRIMARY KEY,name VARCHAR(60),name_eng VARCHAR(60),speed_profile INTEGER);

:

.

. , .

( , ) 60 .

speed_profile .

. :

SELECT AddGeometryColumn('health_services','road_net','the_geom',4121,'LINESTRING',2);

AddGeometryColumn . AddGeometryColumn :

(health_services) (road_net) (the_geom)

(4121, 87) (, ,

, , , - (multi-polygons) (geometry collections)). (LINESTRING).

(2). :

ALTER TABLE health_services.road_net ADD CONSTRAINT geom_valid_check CHECK (isvalid(the_geom));

(health_services.road_net)

. (geom_valid check).

34

(the_geom).

: CREATE INDEX road_net_idx ON health_services.road_net USING GIST (the_geom);

road_net_idx. (health_services.road_net). (GIST)

(the_geom).

INSERT. :

INSERT INTO . VALUES ( 1, 2, ...., , GeomFromText('LINESTRING( 1, 2,..... ,)', ));

:

INSERT INTO health_services.road_net VALUES (101,'-','THESSALONIKIS-MALGARWN',10.25, GeomFromText('LINESTRING(19232578.31 4929703.03, 19237529.19 4933056.09, 19240777.92 4933359.13, 19245128.96 4933842.78)',4121));

INSERT INTO health_services.road_net VALUES (102,' ','NEA DYTIKI EISODOS',14.25, GeomFromText('LINESTRING(19245128.96 4933842.78, 19246145.94 4933791.02, 19247162.92 4933490.83, 19248471.59 4932704.17, 19249220.53 4932352.26, 19249527.99 4932031.42, 19250576.51 4931513.95)',4121));

INSERT INTO health_services.road_net VALUES (203,'28 ','28is OCTOVRIOU' ,10, GeomFromText('LINESTRING(19247162.92 4933490.83,19248038 4932538.56,19248321.81 4932021.07,19249693.55 4931565.7,19250576.51 4931513.95)',4121));

35

INSERT INTO health_services.road_net VALUES (204,'','LAGKADA',06, GeomFromText('LINESTRING(19250576.51 4931513.95,19251065.75 4931618.74,19251099.74 4933180.61,19250941.12 4933894.7,19251462.31 4936067.03,19251473.64 4937004.56,19251507.63 4937287.32,19252448.04 4939609.27,19253886.98 4942378.48)',4121));

INSERT INTO health_services.road_net VALUES (205,'','MONASTIRIOU',08, GeomFromText('LINESTRING(19236699.04 4941127.77,19239055.72 4940353.61,19240551.31 4940145.19,19241140.48 4939430.64,19241389.75 4938775.69,19245559.27 4936037.27,19246714.95 4935114.71,19247598.71 4933835.19,19251065.75 4931618.74)',4121));

INSERT INTO health_services.road_net VALUES (206,'','EGNATIA',07, GeomFromText('LINESTRING(19240777.92 4933359.13,19239690.22 4936453.93,19239690.22 4938507.76,19241140.48 4939430.64,19241888.28 4939847.45,19252448.04 4939609.27,19254306.2 4939400.87,19254351.52 4938924.54,19253626.38 4938388.69,19253513.08 4937852.87,19253603.72 4937153.38)',4121));

INSERT INTO health_services.road_net VALUES (207,' ','PERIFEREIAKI LEOFOROS',09, GeomFromText

('LINESTRING( 19245128.96 4933842.78,19245106.06 4935367.66,19245559.27 4936037.27,19246556.33 4936945.03,19247779.99 4937093.85,19251473.64 4937004.56,19252244.1 4937421.26,

36

19253603.72 4937153.38,19253988.95 4935992.63,19254351.52 4935129.59,19254759.4 4934742.74,19254510.14 4933522.77,19254918.03 4931588.99,19255529.86 4929982.76,19256209.67 4929120.26,19256504.26 4928049.68,19257048.11 4927722.58,19258022.51 4927633.38,19258226.45 4927365.76,19258135.81 4925938.61,19257523.98 4924690.02,19255756.46 4922995.77,19254918.03 4922252.77)',4121));

INSERT INTO health_services.road_net VALUES (208,' ','ETHNIKIS ANTISTASEOS',05, GeomFromText

('LINESTRING(19254918.03 4922252.77,19254487.48 4922995.77,19253966.29 4923946.89)',4121));

INSERT INTO health_services.road_net VALUES (209,' ','VASSILISIS OLGAS',07, GeomFromText('LINESTRING(19253966.29 4923946.89,19253467.76 4924749.47,19252969.23 4926414.3,19253195.83 4928406.53,19252969.23 4929625.85)',4121));

INSERT INTO health_services.road_net VALUES (210,'','TSIMISKI',06, GeomFromText('LINESTRING(19252969.23 4929625.85,19250576.51 4931513.95)',4121));

INSERT INTO health_services.road_net VALUES (211,'','EGNATIA',08, GeomFromText('LINESTRING(19251065.75 4931618.74,19253445.1 4929953.01,19254056.93 4929179.74,19254419.5 4924600.84,19255756.46 4922995.77)',4121));

INSERT INTO health_services.road_net VALUES (212,' ','ELEFTHERIOU VENIZELOU',05, GeomFromText

37

('LINESTRING(19254487.48 4922995.77,19253671.7 4923382.15,19253150.51 4923887.44)',4121));

INSERT INTO health_services.road_net VALUES (213,' ','MEGALOU ALEKSANDROU',07, GeomFromText

('LINESTRING(19253150.51 4923887.44,19253037.21 4925135.93,19252674.64 4926146.72,19252991.89 4928406.53,19252923.91 4929150)',4121));

INSERT INTO health_services.road_net VALUES (214,' ','LEOFOROS NIKIS',06, GeomFromText('LINESTRING(19252923.91 4929150,19251994.83 4930101.73,19250997.77 4930875.08,19250576.51 4931513.95)',4121));

. :

CREATE TABLE health_services.hospitals(ID INTEGER PRIMARY KEY, NAME VARCHAR(70) );

SELECT AddGeometryColumn('health_services','hospitals','the_geom',4121,'POINT',2);

ALTER TABLE health_services.hospitals ADD CONSTRAINT hospitals_valid_check CHECK (isvalid(the_geom));

CREATE INDEX hospitals_idx ON health_services.hospitals USING GIST (the_geom);

SQL :

INSERT INTO health_services.hospitals VALUES (200,' ',GeomFromText('POINT(19252515.21 4933565.18)',4121));INSERT INTO health_services.hospitals VALUES (201,' ',GeomFromText('POINT(19253596.71 4930995.65)',4121));INSERT INTO health_services.hospitals VALUES (202,' ',GeomFromText('POINT

38

(19253527.68 4926493.21)',4121));INSERT INTO health_services.hospitals VALUES (203,' ',GeomFromText('POINT(19253865.17 4929898.8)',4121));

. :

CREATE TABLE health_services.municipal(id INTEGER PRIMARY KEY, name VARCHAR(30));

SELECT AddGeometryColumn('health_services', 'municipal','the_geom',4121,'POLYGON',2);

ALTER TABLE health_services.municipal ADD CONSTRAINT geom_valid_check CHECK (isvalid(the_geom));

CREATE INDEX municipal_idx ON health_services.municipal USING GIST (the_geom)

:

INSERT INTO health_services.municipal VALUES (400,'', GeomFromText('POLYGON((19252337.28 4924473.456,19252400.28 4929709.089,19248621.84 4931397.553,19247754.52 4930485.015,19247176.54 4931934.153,19247087.17 4933316.181,19249196.15 4933179.604, 19250922.02 4932784.313, 19251061.93 4933355.616, 19251240.67 4932719.875,19251378.39 4932853.56, 19253251.49 4932012.049,19254181.08 4932068.789,19253488.1 4930723.478,19254917.28 4930153.292, 19254945.12 4928520.803, 19255963.35 4928880.35, 19257276.79 4927892.109, 19254963.434 4923695.129,19252337.28 4924473.456))',4121));

: . ( 19252337.28 4924473.456) . .

39

pgAdminIII Delete/Drop. hospitals .

SQL. municipal:

DROP TABLE health_services.municipal

.

, :

DELETE FROM health_services.municipal

40

5.1.4 *.shp

5.1.4.1 command line

PostGIS (command line tool) *.shp PostgreSQL/PostGIS. shp2pgsql.

hospitals.shp .

PATH bin PostgreSQL.

Start, My computer, Properties, Advanced, Environment Variables, New,

Variable name: PATHVariable value: c:\Program Files\PostgreSQL\8.3\bin\

OK.

41

hospitals.shp. c:\Temp\.

: *.shp (shapefiles) . , C:\temp , hospitals.shp. *.shp, *.prj *.dbf, *.cpg, *.sbn *.shx. , hospitals.

, :

shp2pgsql.exe -cDI -s4121 -W UTF-8 hospitals hospitals | psql -d thessaloniki -U postgres

enter

42

*.shp hospitals .

shp2pgsql.exe -cDI -s 4121 hospitals hospitals | psql -d thessaloniki -U postgres:

(shp2pgsql.exe -cDI -s 4121 hospitals hospitals) SQL .

c . a .

-D PostgreSQL "dump" .

-I GiST . . .

-s (SRID) , 4121.

hospitals .

hospitals .

( psql -d thessaloniki -U postgres) psql PostgreSQL SQL . d . U .

(public) . hospitals public health_services. SQL :

43

CREATE TABLE health_services.hospitalsAS (SELECT * FROM public.hospitals);ALTER TABLE health_services.hospitals ADD CONSTRAINT hospitals_pkey PRIMARY KEY (gid);CREATE INDEX health_services_idx ON health_services.hospitals USING GIST (the_geom);DROP TABLE public.hospitals;

: shp2pgsql.exe . *.sql insert dump . psql .

5.1.4.2 QuantumGIS:

QuantumGIS *.shp PostgreSQL/PostGIS.

QuantumGIS Start, All programs, QuantumGIS, QuantumGIS.

PostgreSQL/PostGIS . ( ) Plugins, Manage plugins SPIT :

.

44

Plugins, SPIT, Import Shapefiles to PostgreSQL.

.

45

*.shp. New .

Test Connect . .

Create a new PostGIS connection

SPIT Thessaloniki Connect.

- Use Default SRID or specify here -1 4121 .

Add . (UTF-8).

46

SPIT .

47

.

5.1.4.3 QuantumGIS

QuantumGIS :

QuantumGIS .

Layer, Add PostGIS Layer New. QuantumGIS PostgreSQL/PostGIS, .

.

Connect. . / Add.

48

QuantumGIS.

49

5.1.4.4 *.shp

PostgreSQL *.shp. pgsql2shp. : *.shp c:\export . c:\export.

50

: pgsql2shp -P5678 -u postgres thessaloniki health_services.hospitals

enter

:

pgsql2shp -P5678 -u postgres thessaloniki health_services.hospitals

pgsql2shp: pgsql2shp.exe -P5678: - ( 7, : 4.1

51

PostgreSQL/PostGIS) -u postgres: -u thessaloniki: health_services.hospitals:

.

5.1.5

. . CREATE TABLE INSERT. . Quantum GIS .

*.dbf , . ( ), ID . . .

*.csv ( ). Open Office/scalq. , (File Save as Text CSV (.csv)) , :

52

c:/TEMP/hospital_names_latin.csv .

.

:

create table hospitals_latin (ID NUMERIC PRIMARY KEY, NAME VARCHAR);

*.csv .

copy hospitals_latin from 'c:/TEMP/hospital_names_latin.csv' DELIMITERS ',' CSV;

.

5.1.6

, . 1987 (87). 1984 (WGS84). (SRID Spatial Reference ID) . 87 4121. WGS84 4326. spatial_ref_sys public .

Quantum GIS

53

change CRS

SQL:

SELECT updateGeometrySRID('health_services', 'hospitals', 'the_geom', 4326);

UPDATE health_services.hospitals set the_geom =transform(SetSRID(the_geom, 4121), 4326);

, . .

5.2

PostgreSQL/PostGIS . . , . :

54

SELECT * FROM health_services.hospitals;

( ) .

. .

5.2.1 SQL

, . : ;

SELECT * FROM health_services.municipalWHERE "NAME" = '';

,

55

40.000

SELECT * FROM health_services.municipalWHERE "POP" < 40000;

40,000 10,000

SELECT * FROM health_services.municipalWHERE "POP" < 40000AND "POP" > 10000;

SELECT * FROM health_services.municipalWHERE "POP" < 40000AND "POP" > 10000ORDER BY "NAME" ASC;

56

SELECT * FROM health_services.municipalWHERE "POP" < 40000AND "POP" > 10000ORDER BY POP DESC;

: . SELECT *. SELECT .

SQL . , (. : ) .

5.2.2 QuantumGIS

QuantumGIS SQL . Layer, Add PostGIS Layer . Connect. . . SQL. SQL .

57

, , 40,000 10,000 . thessaloniki Connect. . municipal SQL. : "POP" < 40000 AND "POP" > 10000

municipal. 10000 40000 .

58

5.2.3

. .

5.2.3.1 WITHIN CONTAINS

WITHIN CONTAINS .

WITHIN :

SELECT X FROM A,B WHERE WITHIN (Geom.A, GeomB)

CONTAINS :

SELECT X

59

FROM A,B WHERE CONTAINS (Geom., Geom)

.

WITHIN ( ) : () (19254196 4927496);

SELECT "NAME"FROM health_services.municipalWHERE WITHIN( GeomFromText('POINT(19254196 4927496)',4121), municipal.the_geom);

;

SELECT *FROM health_services.hospitals WHERE WITHIN(the_geom, (SELECT the_geom FROM health_services.municipal WHERE "NAME" =''));

;

SELECT *FROM health_services.road_net WHERE WITHIN(the_geom, (SELECT the_geom FROM health_services.municipal WHERE "NAME" = ''));

60

;

SELECT hospitals.name, municipal."NAME"FROM health_services.hospitals, health_services.municipalWHERE WITHIN (hospitals.the_geom, municipal.the_geom);

: , QuantumGIS . . :

CREATE VIEW health_services.hospitals_thessaloniki AS(SELECT *FROM health_services.hospitals WHERE WITHIN(the_geom, (SELECT the_geom FROM health_services.municipal WHERE "NAME"

61

='')));

. .

CONTAINS. ;

SELECT "NAME"FROM health_services.municipalWHERE CONTAINS(the_geom, (SELECT the_geom FROM health_services.hospitals WHERE hospitals.name=' '));

;

SELECT hospitals.name, municipal."NAME"FROM health_services.hospitals, health_services.municipalWHERE CONTAINS(municipal.the_geom, hospitals.the_geom);

62

5.2.3.2 DISTANCE

DISTANCE ( ) :

2000 (19254196 4927496) ;

SELECT name, DISTANCE(the_geom, GeomFromText('POINT(19254196 4927496)',4121)) AS distFROM health_services.hospitalsWHERE DISTANCE(the_geom, GeomFromText('POINT(19254196 4927496)',4121))

SELECT H1.name AS Hospital1, H2.name AS Hospital2, DISTANCE(H1.the_geom, H2.the_geom) AS distanceFROM health_services.hospitals H1, health_services.hospitals H2WHERE DISTANCE(H1.the_geom, H2.the_geom)

4931471.32450980,19260523.58872549 4931624.24705882))',4121) );

(19260523.58872549 4931624.24705882, 19252724.53872549 4925125.03872549, 19253794.99656863 4913350.00245098, 19268934.32892157 4931471.32450980, 19260523.58872549 4931624.24705882);

SELECT municipal."NAME"FROM health_services.municipalWHERE INTERSECTS (the_geom, GeomFromText('POLYGON((19260523.58872549 4931624.24705882, 19252724.53872549 4925125.03872549, 19253794.99656863 4913350.00245098, 19268934.32892157 4931471.32450980,19260523.58872549 4931624.24705882))',4121) );

;

SELECT road_net.name, municipal."NAME"FROM health_services.road_net, health_services.municipalWHERE INTERSECTS (municipal.the_geom, road_net.the_geom)

65

;

SELECT road_net.name, count (*) FROM health_services.road_net, health_services.municipalWHERE INTERSECTS (municipal.the_geom, road_net.the_geom)GROUP BY road_net.name

5.2.3.4 TOUCHES

TOUCHES . :

; SELECT M1."NAME", M2."NAME"FROM health_services.municipal M1, health_services.municipal M2WHERE TOUCHES(M1.the_geom, M2.the_geom)AND M1."ID" < M2."ID";

, ;

SELECT M1."NAME", M2."NAME"FROM health_services.municipal M1, health_services.municipal M2

66

WHERE TOUCHES(M1.the_geom, M2.the_geom)AND M1."ID" < M2."ID"AND M1."NAME" = '';

;

SELECT R1.name, R2.nameFROM health_services.road_net R1, health_services.road_net R2WHERE TOUCHES(R1.the_geom, R2.the_geom)AND R1.id < R2.id;

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5.2.3.5 AREA

.

..

SELECT "NAME", area(the_geom) AS municipal_areaFROM health_services.municipalORDER BY municipal_area DESC;

;

SELECT * FROM (SELECT "NAME", area(the_geom) AS municipal_areaFROM health_services.municipalORDER BY municipal_area desc)AS FOOLIMIT 1;

5.2.3.6 ENVELOPE

.

SELECT "NAME", AsText(envelope(the_geom)) AS bounding_boxFROM health_services.municipal;

: , , , .

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5.2.3.7 LENGTH

LENGTH . , road_net?

SELECT name, length(the_geom) AS segment_length FROM health_services.road_netORDER BY segment_length DESC;

:

SELECT name, sum(length(the_geom)) AS segment_length FROM health_services.road_netGROUP by nameORDER BY segment_length DESC;

5.2.3.8 NPOINTS

.

, road_net;

SELECT name, npoints(the_geom) AS vertexesFROM health_services.road_netORDER BY vertexes DESC;

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5.3

5.3.1 QuantumGIS

:

/ (legend) .

Layer, Toggle Editing.

, .

.

5.3.1.1

Edit, Capture Line (Point/Polygon ).

.

70

. .

71

5.3.1.2

Edit Delete Selected.

5.3.1.3

. Edit Move Feature. .

5.3.1.4

. Edit Split Features. .

5.3.1.5

.

72

Edit Add Vertex. .

5.3.1.6

. Edit Delete Vertex. .

5.3.1.7 .

, /. Open attribute table. . enter.

Layer Toggle Editing. . .

Save . Discard .

5.3.2 UDIG

QuantumGIS PostgreSQL/PostGIS. UDIG. PostgreSQL/PostGIS UDIG.

UDIG . http://udig.refractions.net/files/downloads/udig-1.1.1.exe . : http://udig.refractions.net/users/. , Start--> All Programs UDIG1.1.1--> Udig.

project .

73

project.

project (thessaloniki) (C:\uDig\projects\)

74

health services.

75

. . WGS84 ' (by default) .

WGS84 4121 87.

76

. (health services) Add...

PostGIS

QuantunGIS.

77

Finish

78

. show all data ( window) Table show selection. ' - .

uDig . (, , ) (. ).

79

. . . .

, , . .

.

Edit Rollback.

, , Edit commit. .

80

, UDIG (legend), (Grid) (scalebar). Layer, Legend/Layer, Grid/Layer, Scalebar.

81

6.

6.1 PL/pgSQL

PL/pgSQL (Procedural Language/PostgreSQL Structured Query Language) PostgreSQL. PL/pgSQL PostgreSQL . : PL/Java, PL/Perl, plPHP, PL/Python, PL/R, PL/Ruby, PL/sh, PL/Tcl.

PL/pgSQL PL/SQL Oracle. PL/pgSQL :

- ,

- SQL

-

- ,

-

-

PL/pgSQL (built-in functions). (conditional computation functions) (operators) (index expressions).

PL/pgSQL , SQL, . PL/pgSQL SQL .

PL/pgSQL SQL

82

(client/server communication overhead).

:

- .

- .

- .

- (functions). PL/pgSQL , SQL.

PL/pgSQL . .

6.2 PL/pgSQL

PL/pgSQL . ( ). . . . . . . ( ) .

. incidents. :

/ .

.

.

.

.

:

CREATE TABLE health_services.incidents

83

(gid Integer PRIMARY KEY,time TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,near_hosp_name character varying(200),dist NUMERIC);

SELECT AddGeometryColumn('health_services','incidents','the_geom','4121','POINT',2);

( ) SQL :

INSERT INTO health_services.incidents VALUES (/,CURRENT_TIMESTAMP, 9999, 9999, GeomFromText('POINT( )',4121));

. CURRENT_TIMESTAMP. 9999 ( ) .

6.2.1

:

. ( ) . . .

SQL:

LATEST_INCIDENT_ID = (SELECT gidFROM health_services.incidentsORDER BY time desclimit 1);

. DISTANCE :

NEAREST_HOSP = (SELECT hospital FROM (SELECT name AS Hospital, DISTANCE(H.the_geom, I.the_geom) AS distanceFROM health_services.hospitals H, health_services.incidents IWHERE I.gid = LATEST_INCIDENT_IDORDER BY DISTANCE asc) AS NEARBY_HOSPITALSlimit 1);

84

:

HOSP_DIST = (SELECT DISTANCE FROM (SELECT name AS Hospital, DISTANCE(H.the_geom, I.the_geom) AS distanceFROM health_services.hospitals H, health_services.incidents IWHERE I.gid = LATEST_INCIDENT_IDORDER BY DISTANCE asc) AS NEARBY_HOSPITALSlimit 1);

. SQL:

UPDATE health_services.incidentsSET near_hosp_name = NEAREST_HOSP, dist = HOSP_DISTWHERE GID = LATEST_INCIDENT_ID;

PL/pgSQL :

CREATE OR REPLACE FUNCTION FIND_NEAREST_HOSPITAL() RETURNS trigger AS '

DECLARELATEST_INCIDENT_ID INTEGER;NEAREST_HOSP character varying(200);HOSP_DIST NUMERIC;

BEGIN



HOSP_DIST = (SELECT DISTANCE FROM (SELECT name AS Hospital, DISTANCE(H.the_geom, I.the_geom) AS distanceFROM health_services.hospitals H, health_services.incidents IWHERE I.gid = LATEST_INCIDENT_IDORDER BY DISTANCE asc) AS NEARBY_HOSPITALSlimit 1);

UPDATE health_services.incidents

85

SET near_hosp_name = NEAREST_HOSP, dist = HOSP_DISTWHERE GID = LATEST_INCIDENT_ID;

RETURN new;END'Language plpgsql;

pgAdminIII. :

Query returned successfully with no result in ... ms

SQL :

CREATE OR REPLACE FUNCTION FIND_NEAREST_HOSPITAL() RETURNS trigger AS '

, , (. ) .

, .

DECLARELATEST_INCIDENT_ID INTEGER;NEAREST_HOSP character varying(200);HOSP_DIST NUMERIC;

.

BEGIN



HOSP_DIST = (SELECT DISTANCE FROM (SELECT name AS Hospital, DISTANCE(H.the_geom, I.the_geom) AS distanceFROM health_services.hospitals H, health_services.incidents IWHERE I.gid = LATEST_INCIDENT_ID

86

ORDER BY DISTANCE asc) AS NEARBY_HOSPITALSlimit 1);

LATEST_INCIDENT_ID

NEAREST_HOSP .

HOSP_DIST .

(LATEST_INCIDENT_ID) (NEAREST_HOSP, HOSP_DIST).

UPDATE health_services.incidentsSET near_hosp_name = NEAREST_HOSP, dist = HOSP_DISTWHERE GID = LATEST_INCIDENT_ID;

NEAREST_HOSP HOSP_DIST .

RETURN new;END'Language plpgsql;

PL/pgSQL CREATE FUNCTION . new (. http :// www . postgresql . org / ons /8.3/ interactive / plpgsql - trigger . html ). Pl/pgSQL.

6.2.2

. . . INSERT incidents .

:

CREATE TRIGGER FIND_NEAREST_HOSPITAL AFTER INSERT ON health_services.incidentsFOR EACH ROW EXECUTE PROCEDURE FIND_NEAREST_HOSPITAL();

pgAdminIII, . :

SQL incidents.

87

.

INSERT INTO health_services.INCIDENTS VALUES (001,CURRENT_TIMESTAMP, 9999, 9999, GeomFromText('POINT(19257758.86538117 4931260.15004108)',4121));



. incidents. QuantumGIS.

, (incidents) INSERT. , ( near_hosp_name dist).

88

7.

, ( ) . PostgreSQL/PostGIS/QuantumGIS. . , , , , , . INSERT, shp2pgsql QuantumGIS, shapefile. QuantumGIS . , QuantumGIS SQL. WITHIN/CONTAINS, DISTANCE, INTERSECTS, TOUCHES AREA, LENGTH, ENVELOPE, NPOINTS.

89

8.

PostgreSQL: http://www.postgresql.org/docs/

PostGIS: http://postgis.refractions.net/documentation/

QuantumGIS: http://www.qgis.org/en/documentation.htmlhttp://www.qgis.org/en/documentation.html

Open GIS Consortium, Inc. OpenGIS Simple Features Specification For SQL. Revision 1.1 OpenGIS Project Document 99-049. May 05/05/1999. http://portal.opengeospatial.org/files/?artifact_id=829

Ramsey, P. Introduction to PostGIS: Workshop prepared for the FOSS4G 2007: http://2007.foss4g.org/workshops/W-04/

Boston GIS, Part 1: Getting Started With PostGIS: An almost Idiot's Guide. http://www.bostongis.com/PrinterFriendly.aspx?content_name=postgis_tut01

, PostgreSQL PostGIS , , .http :// www . dblab . ece . ntua . gr /~ kpatro / geodb / examples / GeoDB 2008_ PostGIS _ Lab . pdf http :// www . dblab . ece . ntua . gr /~ kpatro / geodb / examples / GeoDB 2008_ PostgreSQL _ Lab . pdf

SQL: http :// www . freestuff . gr / forums / viewtopic . php ? t =15660 http :// www . survey . ntua . gr / main / courses / general / dbintro / lectures / db 2005_ lecture 07.

pdf http :// www . cs . uoi . gr /~ pitoura / db 2000/ sql 2/ index . htm

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1. 2. : .3. 3.1 PostgreSQL3.2 PostGIS3.3 QuantumGIS

4. 4.1 PostgreSQL/PostGIS4.2 QuantumGIS

5. 5.1. 5.1.1 5.1.1.1 (template) 5.1.1.2 (template) 5.1.1.3

5.1.2 5.1.3 SQL5.1.4 *.shp5.1.4.1 command line 5.1.4.2 QuantumGIS:5.1.4.3 QuantumGIS5.1.4.4 *.shp

5.1.5 5.1.6

5.2 5.2.1 SQL 5.2.2 QuantumGIS5.2.3 5.2.3.1 WITHIN CONTAINS5.2.3.2 DISTANCE5.2.3.3 INTERSECTS5.2.3.4 TOUCHES5.2.3.5 AREA5.2.3.6 ENVELOPE5.2.3.7 LENGTH 5.2.3.8 NPOINTS

5.3 5.3.1 QuantumGIS 5.3.1.1 5.3.1.2 5.3.1.3 5.3.1.4 5.3.1.5 5.3.1.6 5.3.1.7 .

5.3.2 UDIG

6. 6.1 PL/pgSQL6.2 PL/pgSQL6.2.1 6.2.2

7. 8.

Documents

Postgis Qgis Gr 2.0