我正试图使用GNAT CE 2019查询PostgreSQL数据库。我的数据库中有两个表，汽车和人。
mydb1-# \dt
List of relations
Schema | Name | Type | Owner
--------+--------+-------+----------
public | car | table | postgres
public | person | table | postgres
(2 rows)
我想执行一个简单的Select语句，当我在终端使用psql执行时，返回的是这个。
mydb1=# SELECT * FROM Person;
person_uid | first_name | last_name | gender | email | date_of_birth | country_of_birth | car_uid
--------------------------------------+------------+------------+--------+------------------------------+---------------+------------------+--------------------------------------
75f5e55d-12b2-463e-93ff-1c921e44c3e1 | Audrie | Vasyukov | Female | [email protected] | 1988-11-24 | Guatemala |
9e3f7f90-6e9a-4f2d-ae4e-c852d819ed33 | Nefen | Philippard | Male | [email protected] | 2006-11-08 | Russia |
ffad6113-2321-47c3-8e1d-b8bbe1f7ffa1 | Leonore | Garthland | Female | [email protected] | 1991-03-23 | Canada |
268c1977-a5cc-4794-9cdd-e0e4af7890b9 | Yank | Turfitt | Male | [email protected] | 1990-02-07 | China |
3c815fa3-74b9-493a-9466-f32010806b16 | Benn | Pawley | Male | [email protected] | 2006-10-28 | Russia |
690fc9e9-309e-4d70-8dab-167653b99763 | Tod | Easen | Male | [email protected] | 1990-08-24 | China | 5fa7490e-ba42-4a96-b806-097bbb16e30e
然而，我想在GNAT CE 2019中执行这个操作。这是我的main.adb文件目前的样子。
with GNATCOLL.SQL.Postgres; use GNATCOLL.SQL.Postgres;
with GNATCOLL.SQL.Exec; use GNATCOLL.SQL.Exec;
with GNATCOLL.VFS; use GNATCOLL.VFS;
with GNATCOLL.SQL.Inspect; use GNATCOLL.SQL.Inspect;
with GNATCOLL.SQL; use GNATCOLL.SQL;
procedure Main is
-- Datebase Description
--
DB_Descr : GNATCOLL.SQL.Exec.Database_Description;
-- Database Connection
--
DB : GNATCOLL.SQL.Exec.Database_Connection;
-- Used to Query the data
--
Q : SQL_Query;
begin
-- Database Description
--
DB_Descr := GNATCOLL.SQL.Postgres.Setup ("mydb1", "parallels", "localhost", "MyPassword", 5432);
-- Database Connection
--
DB := DB_Descr.Build_Connection;
-- Query the data
--
Q := SQL_Select
(Fields => Person.first_name,
From => Person);
Free (DB); -- for all connections you have opened
Free (DB_Descr);
end Main;
当我试图连接数据库时 进程成功终止了。
我不确定应该使用Select语句的语法。Name SELECT * FROM Person; 从GNAT CE 2019内的声明，这将是非常感激。
谢谢你，劳埃德
新增130520
parallels@localhost gnatcoll_db2ada]$ ls
dborm.py gnatcoll-db2ada-main-generate.adb
dbschema.txt gnatcoll_postgres2ada.adb
gnatcoll_all2ada.adb gnatcoll_postgres2ada.gpr
gnatcoll_all2ada.gpr gnatcoll_sqlite2ada.adb
gnatcoll_db2ada.adb gnatcoll_sqlite2ada.gpr
gnatcoll-db2ada.ads Makefile
gnatcoll_db2ada.gpr makefile.setup
[parallels@localhost gnatcoll_db2ada]$ gnatcoll_postgres2ada -dbmodel dschema.txt/home/parallels/Desktop/dschema.txt
bash: gnatcoll_postgres2ada: command not found...
[parallels@localhost gnatcoll_db2ada]$
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prbuild -d -P/home/parallels/Documents/Ada Projects/TEST/default.gpr -XGNATCOLL_OS=unix -XBUILD=PROD -XGNATCOLL_HASPQPREPARE=yes -XGPR_BUILD=static -XLIBRARY_TYPE=static -XXMLADA_BUILD=static -XGNATCOLL_CORE_BUILD=static -XGNATCOLL_BUILD=static /home/parallels/Documents/Ada Projects/TEST/src/main.adb
Compile
[Ada] main.adb
Bind
[gprbind] main.bexch
[Ada] main.ali
Link
[link] main.adb
/home/parallels/opt/GNAT/2019/bin/../libexec/gcc/x86_64-pc-linux-gnu/8.3.1/ld: cannot find -lpq
collect2: error: ld returned 1 exit status
gprbuild: link of main.adb failed
gprbuild: failed command was: /home/parallels/opt/GNAT/2019/bin/gcc main.o b__main.o /home/parallels/Documents/Ada Projects/TEST/obj/database_names.o /home/parallels/Documents/Ada Projects/TEST/obj/database.o /home/parallels/gnatcoll-db/postgres/lib/static/libgnatcoll_postgres.a /home/parallels/gnatcoll-db/sql/lib/static/libgnatcoll_sql.a /home/parallels/opt/GNAT/2019/lib/gnatcoll.static/libgnatcoll.a /home/parallels/opt/GNAT/2019/lib/gpr/static/gpr/libgpr.a /home/parallels/opt/GNAT/2019/lib/xmla
da/xmlada_schema.static/libxmlada_schema.a /home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_dom.static/libxmlada_dom.a /home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_sax.static/libxmlada_sax.a /home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_input.static/libxmlada_input_sources.a /home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_unicode.static/libxmlada_unicode.a -lpq -L/home/parallels/Documents/Ada Projects/TEST/obj/ -L/home/parallels/Documents/Ada Projects/TEST/obj/ -L/home/parallels/gnatcoll-db/p
ostgres/lib/static/ -L/home/parallels/opt/GNAT/2019/lib/gnatcoll.static/ -L/home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_dom.static/ -L/home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_sax.static/ -L/home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_unicode.static/ -L/home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_input.static/ -L/home/parallels/opt/GNAT/2019/lib/xmlada/xmlada_schema.static/ -L/home/parallels/opt/GNAT/2019/lib/gpr/static/gpr/ -L/home/parallels/gnatcoll-db/sql/lib/static/ -L/home/par
allels/opt/GNAT/2019/lib/gcc/x86_64-pc-linux-gnu/8.3.1/adalib/ -static-libgcc /home/parallels/opt/GNAT/2019/lib/gcc/x86_64-pc-linux-gnu/8.3.1/adalib/libgnarl.a /home/parallels/opt/GNAT/2019/lib/gcc/x86_64-pc-linux-gnu/8.3.1/adalib/libgnat.a -lrt -lpthread -ldl -Wl,-rpath-link,/home/parallels/opt/GNAT/2019/lib/gcc/x86_64-pc-linux-gnu/8.3.1//adalib -Wl,-z,origin,-rpath,$ORIGIN/:$ORIGIN/../../../..//gnatcoll-db/postgres/lib/static:$ORIGIN/../../../..//opt/GNAT/2019/lib/gnatcoll.static:$ORIGIN/../../
../..//opt/GNAT/2019/lib/xmlada/xmlada_dom.static:$ORIGIN/../../../..//opt/GNAT/2019/lib/xmlada/xmlada_sax.static:$ORIGIN/../../../..//opt/GNAT/2019/lib/xmlada/xmlada_unicode.static:$ORIGIN/../../../..//opt/GNAT/2019/lib/xmlada/xmlada_input.static:$ORIGIN/../../../..//opt/GNAT/2019/lib/xmlada/xmlada_schema.static:$ORIGIN/../../../..//opt/GNAT/2019/lib/gpr/static/gpr:$ORIGIN/../../../..//gnatcoll-db/sql/lib/static:$ORIGIN/../../../..//opt/GNAT/2019/lib/gcc/x86_64-pc-linux-gnu/8.3.1/adalib -o main
[2020-05-15 14:56:50] process exited with status 4, 100% (30/30), elapsed time: 02.34s
已添加170520
[SQL.ERROR] FATAL: Ident authentication failed for user "postgres"
_SQL.ERROR_ FATAL: Ident authentication failed for user "postgres"
_SQL.ERROR_ params="dbname='mydb1' user='postgres' host='localhost' sslmode=allow" ()
[SQL.ERROR] Failed to execute SELECT persons.person_uid, persons.first_name, persons.last_name, persons.gender, persons.email, persons.date_of_birth, persons.country_of_birth FROM persons error=No connection to database
FAILED
[2020-05-17 19:30:04] process terminated successfully, elapsed time: 00.19s
新增290520
home/parallels/Documents/Ada Projects/Connect to a DB/obj/main
[SQL.ERROR] select failed: SELECT persons.person_uid, persons.first_name, persons.last_name, persons.gender, persons.email, persons.date_of_birth, persons.country_of_birth FROM persons PGRES_FATAL_ERROR ERROR: relation "persons" does not exist
_SQL.ERROR_ LINE 1: ...persons.date_of_birth, persons.country_of_birth FROM persons
_SQL.ERROR_ ^
FAILED
[2020-05-29 22:40:11] process terminated successfully, elapsed time: 00.19s
postgres=# select * from persons;
person_uid | first_name | last_name | gender | email | date_of_birth | country_of_birth
--------------------------------------+------------+------------+--------+------------------------------+---------------+------------------
afbf64be-e7d5-45a1-b8fb-1a9fd66e2765 | Audrie | Vasyukov | Female | [email protected] | 1988-11-24 | Guatemala
ffda7264-1e54-428b-ae68-9ddb7b97702a | Nefen | Philippard | Male | [email protected] | 2006-11-08 | Russia
169d5fb9-8d40-451e-8b02-cd1c3639fbed | Leonore | Garthland | Female | [email protected] | 1991-03-23 | Canada
e34f4f21-524c-4134-81d6-7fd1fd9a7537 | Yank | Turfitt | Male | [email protected] | 1990-02-07 | China
57336d0e-34f2-4166-a100-7b468e96a521 | Benn | Pawley | Male | [email protected] | 2006-10-28 | Russia
b54a8411-3674-4432-b896-aaf35a10919b | Tod | Easen | Male | [email protected] | 1990-08-24 | China
(6 rows)