Shulou(Shulou.com)06/01 Report--

-sequence sequnece

User_sequneces

Increment by 2-step size

Start with 2-starting value

Maxvalue 10-maximum 2 4 6 8 10

Nomaxvalue

Minvalue 2 minimum

Nominvalue

Cycle cycle

Nocycle

Cache 2 cach

Nocache

Order sorting

Noorder

1 3 5 7 15

Create sequnece seq1 start with 1 increment by 2 maxvalue 15 nocycle

Citation sequence

Current value sequence name. currval

The next value sequence name. Nextval

Create sequence seq3 start with 1 increment by 2 maxvalue 7 cycle

Create sequence seq3 start with 1 increment by 2 maxvalue 6 cycle nocache

Create sequence seq3 start with 3 increment by 2 maxvalue 6

Minvalue 2 cycle nocache

Cache 5

1 2 3 4 5

1 2 3 4 5 6 7 8 9 10 11

-modify sequence properties

New value of ALTER SEQUENCE xx sequence attribute

-temporary watch

Shopping cart-TABLE

(1) transaction end commit rollback

(2) end of session exit

Create global temporary table gwc (price number (4), name varchar2 (20))-transactions

Create global temporary table gwc (price number (4), name varchar2 (20)) on commit preserve rows

-

Constraint constraint

Maintain the integrity of the data

Delete constraint

SQL > ALTER TABLE nn1 DROP CONSTRAINT SYS_C0011064

Five constraints

Non-empty constraint

Unique constraint

Primary key constraint

External constraint

Check constraints-Custom constraint

Non-null constraint-do not allow null values to be inserted

1muri-keyword-NOT NULL

2Murray-Type-C

3Murray-multiple non-empty constraints are allowed in a table

4Murray-non-null constraints will inherit

5Murray-combined column constraints are not supported

Unique constraint-duplicate values are not allowed to be inserted, except for null

1Murray-keyword UNIQUE

2Murray Mutual-Type U

3Murray-multiple unique constraints are allowed in a table

4Murray-the only constraint does not inherit

5Murray-support combinational column constraints

Primary key constraint-non-null + unique

1Murray-keyword primary key

2Murray Mutual-Type P

3Mutual-one primary key constraint for lard in a table

4Murray-constraints do not inherit

5Murray-support combinational column constraints

External constraint

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