Basic SQL
目录
Basic SQL 1
1、Create 1
2、Insert data 5
3、Update data 6
4、Delete data 7
5、Drop 7
6、Where：Simple select with like and between and so on 8
7、Let use function max count sum avg round 9
8、Group by 10
9、Join 13
10、UNIONS 14
11、Filter data by having 16
12、SUB-SELECTS 17
13、Array data 20
1、Create
You can check the created SQL for a table
You can create a table refer other table
Such as
The data will insert into new table automatic
If you don't want data, you can use truncate to delete all data
truncate table "HANA04"."TEST_DB_01"
You can also delete data manually
You can create view by the same way
create view v_test001
as ( select * from "HANA04"."EMPFACT1" )
CREATE VIEW "HANA04"."MY_VIEW01"
( "NAME",
"SDATE",
"SAL_AMT" )
AS SELECT
DEPTNAME AS NAME,
EMPDATE AS SDATE,
SAL AS SAL_AMT
FROM "HANA04"."EMPFACT1",
"HANA04"."EMPFACT2"
WHERE "HANA04"."EMPFACT1"."EMPID" = "HANA04"."EMPFACT2"."EMPID"
WITH READ ONLY
Or
2、Insert data
3、Update data
update "HANA04"."EMPFACT1"
set sal = 888
where empid = 'CC1'
4、Delete data
delete from "HANA04"."EMPFACT1" where empid = 'AA1'
Delete table data
truncate table "HANA04"."TEST_DB_01"
5、Drop
delete table or view
drop table "HANA04"."TEST_DB_01"
drop table "HANA04"."TEST_DB_01" Restrict
drop table "HANA04"."TEST_DB_01" cascade
Restrict: ensures that only tables that do not have relevant views and integrity constraints can be deleted.
cascade: any relevant views and integrity constraints are deleted.
restrict: 确保只有不存在相关视图和 完整性约束的表才能删除
cascade: 任何相关视图和完整性约束一并被删除
