Transcript Databases
Querying Querying Its about asking questions of the database in order to get some results The are 4 different types of queries that we can run Different query types SELECT UPDATE INSERT DELETE (use with care!!) SELECT This query is one which will bring data back from the database, so you’re able to use the information SELECT * FROM tableName WHERE x=y Returned Results id name Dob phone class 356 Jess 3 Mar 1995 12345 678904 5B 412 Hamad 12 Nov 1994 67890 234592 7X 459 Sita 9 Jan 1994 12345 765434 5B 502 James 10 March 09876 65432 6B INSERT This query allows you to add new records into the database table INSERT INTO tableName (column1, column2, column3) VALUES (value1, value2, value3) Returned Results Inserted Correctly – 1 (or true) Not inserted Correctly – 0 (or False) Challenges Bronze Select all of the information out of the film table Silver 1. Select on the data from the film table where the rating is equal to 15 2. Select the data from the directors table where the director is from the USA. Gold Insert another three films into the film table but the films director must be James Cameron or Frank Darabont. You will also have to insert the Directors into the directors table Any SELECT results need to be screen printed and then put into a word document as results. Update This query allows you to update record(s) in the database table UPDATE table_name SET column1=value, column2=value2 WHERE some_column=some_value Returned Results Inserted Correctly – 1 (or true) Not inserted Correctly – 0 (or False) Delete This query allows you to delete record(s) in the database table DELETE FROM tableName WHERE some_column = some_value Returned Results Inserted Correctly – 1 (or true) Not inserted Correctly – 0 (or False) Challenges Bronze There has been a mistake in data that has been entered, and the wrong certification has been awarded to The Dark Knight, it’s now a 15 Silver Das Boot and The good the bad and the ugly need to be removed, update the list to show this Gold Come up with a could of queries of your own, and don’t forget to screenshot them and paste them into your word document.