About Some examples of INSERT INTO
Previously the above table
I want to insert a row
then
INSERT INTO Movies(Id, Title)
VALUES(15,'Hua');
The other three values are null
But if so
INSERT INTO Movies wrote, it would default to include them all, so all have to write up the value of property
VALUES(15, "Hua","Hua",2020,520);
Better yet, all add up, what property you want to add to what to write, even if you also want to add all
最好写成INSERT INTO Movies(Id, Title, Director, Year, Length_minutes)
Then is a UPDATE
UPDATE Movies
SET Director = "Hua", Year = 2020, Length_minutes = 520
WHERE Id = 15 // remember here is 15, instead of '15', here you have to remember to match right, otherwise all the property values in the tuple will be written into the above-Director = "Hua", Year = 2020 , Length_minutes = 520
remember with update and insert the time in the conditions written in adding up the table, or will direct hell broke loose
For example, if the direct write
UPDATE Movies
SET Director = "Hua", Year = 2020, Length_minutes = 520
That he is when you write these letters have all been updated,
So you should first write and then write the WHERE above SET
Plus a map
Then is the DELETE
Note that SQL DELETE statement WHERE clause!
WHERE clause specifies which record or records which need to be removed. If you omit the WHERE clause, all records will be deleted!
For example, to delete rows which just added
DELETE FROM Movies
WHERE Id = 15
To ok
If you want to delete all records
DELETE FROM table_name;
或
DELETE * FROM table_name;
Want to know more about and then delete operations go https://www.runoob.com/sql/sql-delete.html see note below chiefs on the line