sql select select code example

Example 1: sql select from select

SELECT t1.*
FROM   t1
WHERE  t1.MY_FIELD = (SELECT  t2.MY_FIELD
                   FROM    t2
                   WHERE   t2.MY_FIELD = t1.MY_FIELD);

Example 2: sql select syntax

select [all/distinct] <COL1>, <COL2>, <COL3>
from <TABLE_NAME>
[join <JOIN_CONDITION>]
[where <CONDITION>]
[group by <COLUMN_NAME>]
[having <SEARCH_CONDITION>]
[order by <SORT_SPECIFICATION>]


/*
Specifically for SQL -> Oracle

LEGEND: 
[...]   :   optional entries
<...>   :   your specific entry
*/

Example 3: sql select

Used to select data from a database, which is then returned in a results set.
Example 1: Selects all columns from all users.
SELECT * FROM users;
Example 2: Selects the first_name and surname columns
from all users.xx
SELECT first_name, surname FROM users;

Example 4: select in select sql

SELECT column1 = (SELECT column-name FROM table-name WHERE condition),       column-names  FROM table-name WEHRE condition

Example 5: select in select sql

SELECT column-names  FROM table-name1 WHERE value IN (SELECT column-name                   FROM table-name2                   WHERE condition)