postgresql SELECT SELECT using WHERE
Example
In this topic we will base on this table of users :
CREATE TABLE sch_test.user_table
(
id serial NOT NULL,
username character varying,
pass character varying,
first_name character varying(30),
last_name character varying(30),
CONSTRAINT user_table_pkey PRIMARY KEY (id)
)
+----+------------+-----------+----------+------+
| id | first_name | last_name | username | pass |
+----+------------+-----------+----------+------+
| 1 | hello | world | hello | word |
+----+------------+-----------+----------+------+
| 2 | root | me | root | toor |
+----+------------+-----------+----------+------+
Syntax
Select every thing:
SELECT * FROM schema_name.table_name WHERE <condition>;
Select some fields :
SELECT field1, field2 FROM schema_name.table_name WHERE <condition>;
Examples
-- SELECT every thing where id = 1
SELECT * FROM schema_name.table_name WHERE id = 1;
-- SELECT id where username = ? and pass = ?
SELECT id FROM schema_name.table_name WHERE username = 'root' AND pass = 'toor';
-- SELECT first_name where id not equal 1
SELECT first_name FROM schema_name.table_name WHERE id != 1;
