cartesian for checking if something is wrong.

Insert into person (first, last, dob)

insert require record doesn’t exist update require record exists delete require record exists

Select last, first dob from person where dob =

DELETE from person

Truncate - DDL not DML. Removes all rows from a table.

Relations table

contraint Key is a type of constraint. primary key. Not null is a type of constaint is a column constraint Foreign Key not a unique constraint on a table. Foreign key is a contraint on column. UNIQUE key or candidate key. Person and cat

Index represents sorted values can be unique or allow dupes

Normalization Based off OOP. What are the entities we are talking. Classes. Look at things. Abstracting those things to represent in database.

Normal forms The KEY, The WHOLE KEY, and NOTHING BUT the KEY, so help me Codd! Second normal form. Nothing on this table is dependant on the key.

Many to many relationships.

:: type cast