diff --git a/infotro/SDi/labs/database/README.md b/infotro/SDi/labs/database/README.md index feb201f..ea536ce 100644 --- a/infotro/SDi/labs/database/README.md +++ b/infotro/SDi/labs/database/README.md @@ -9,7 +9,8 @@ Lab databases # Queries -#### 1) the description of all Function +### Query 1 +The description of all Function ```sql SELECT `description` FROM `Function` @@ -42,8 +43,10 @@ SELECT `description` FROM `Function` > "Select the source of the input (BD, DVD, HDMI, ...)"
> "Select the Audio format to use with the current source (2ch stereo, 5.1, 7.2, 9.2, ...)"
+---------- -#### 2) the `name` of manufacturers that have at least one entry in the `Model` table +### Query 2 +The `name` of manufacturers that have at least one entry in the `Model` table ```sql SELECT `Manufacturer`.`manufacturerName` FROM `Manufacturer` @@ -58,9 +61,10 @@ WHERE EXISTS( SELECT * > "Sony"
> "Onkyo" +---------- - -#### 3) the `modelName` of device models together with the `manufacturerName` of their manufacturers +### Query 3 +The `modelName` of device models together with the `manufacturerName` of their manufacturers ```sql SELECT `Model`.`modelName`, `Manufacturer`.`manufacturerName` FROM `Model`, `Manufacturer` @@ -76,7 +80,10 @@ WHERE `Model`.`manufacturerID` = `Manufacturer`.`manufacturerID` > "UBP-X800M2","Sony"
> "TX-RZ70","Onkyo" -#### 4) the description of the Function with functionLabel “Stop” +---------- + +### Query 4 +The description of the Function with functionLabel “Stop” ```sql SELECT `Function`.`description` FROM `Function` @@ -86,7 +93,10 @@ WHERE `Function`.`functionLabel` like 'Stop' > "description"
> "Stops the current track" -#### 5) the `functionLabel` for `Function` with `functionID` > 10 and with a `description` containing the word “`preset`” (SQL wildcard character is “`%`”) +---------- + +### Query 5 +The `functionLabel` for `Function` with `functionID` > 10 and with a `description` containing the word “`preset`” (SQL wildcard character is “`%`”) ```sql SELECT `Function`.`functionLabel` FROM `Function` @@ -99,7 +109,10 @@ WHERE `Function`.`functionID` > '10' AND `Function`.`description` like '%preset% > "Preset 3"
> "Save preset" -#### 6) the product of the tables `Code` and `FunctionList` (with and without the `JOIN` keyword), as well as the number of entries in the resulting product table +---------- + +### Query 6 +The product of the tables `Code` and `FunctionList` (with and without the `JOIN` keyword), as well as the number of entries in the resulting product table With JOIN keyword
26 elements in 0,0003 seconds ```sql @@ -174,7 +187,10 @@ WHERE `Code`.`codeID` = `FunctionList`.`codeID`; > "1948573645","4","6"
> "1948573646","1","8" -#### 7) All `codeValue` for `modelID 4` +---------- + +### Query 7 +All `codeValue` for `modelID 4` ```sql SELECT `Code`.`codeValue` FROM `Code` @@ -193,7 +209,10 @@ WHERE `FunctionList`.`modelID` = 4; > "1164736495"
> "1164736496" -#### 8) The number of `codeValue` for `modelID 4` +---------- + +### Query 8 +The number of `codeValue` for `modelID 4` ```sql SELECT COUNT(`Code`.`codeValue`) FROM `Code` @@ -204,7 +223,10 @@ WHERE `FunctionList`.`modelID` = 4; > [!NOTE|label:Result] > 8 -#### 9) All `codeValue` and `functionLabel` for Model with `modelName “SDi-Tuner-01”` +---------- + +### Query 9 +All `codeValue` and `functionLabel` for Model with `modelName “SDi-Tuner-01”` ```sql SELECT `Code`.`codeValue`, `Function`.`functionLabel` FROM `Model` @@ -224,7 +246,10 @@ WHERE `Model`.`modelName` like 'SDi-Tuner-01' > "1164736495","Tune down"
> "1164736496","Tune up" -#### 10) The number of `Function` items per `modelName` +---------- + +### Query 10 +The number of `Function` items per `modelName` ```sql SELECT `Model`.`modelName`, COUNT(`FunctionList`.`functionID`) FROM `Model` @@ -240,8 +265,10 @@ GROUP BY `Model`.`modelName` > "UBP-X800M2","0"
> "TX-RZ70","0" +---------- -#### 11) All `functionLabel` and `description` with their corresponding `modelID`, `functionID` and `codeID`. Be sure to include all `functionLabel` even if they are not used in any device ! +### Query 11 +All `functionLabel` and `description` with their corresponding `modelID`, `functionID` and `codeID`. Be sure to include all `functionLabel` even if they are not used in any device ! ```sql SELECT `Function`.`functionLabel`, `Function`.`description`, `FunctionList`.`modelID`, `FunctionList`.`codeID` FROM `FunctionList` @@ -277,8 +304,10 @@ RIGHT JOIN `Function` ON `FunctionList`.`functionID` = `Function`.`functionID`; > "Input source","Select the source of the input (BD, DVD, HDMI, ...)",NULL,NULL
> "Audio format","Select the Audio format to use with the current source (2ch stereo, 5.1, 7.2, 9.2, ...)",NULL,NULL +---------- -#### 12) All `functionLabel` and `description` of non-used functions in any device. (insert beforehand a new function in `Function`, with no reference in the `FunctionList` table). Add an unused function in the CSV file +### Query 12 +All `functionLabel` and `description` of non-used functions in any device. (insert beforehand a new function in `Function`, with no reference in the `FunctionList` table). Add an unused function in the CSV file ```sql SELECT `Function`.`functionLabel`, `Function`.`description` FROM `FunctionList` @@ -291,18 +320,12 @@ WHERE `FunctionList`.`modelID` is NULL > "Audio format","Select the Audio format to use with the current source (2ch stereo, 5.1, 7.2, 9.2, ...)"
> "Test Function","This function should not be referenced in the FunctionList" - -#### 13) Add a VIEW to your DB to list all HEVs appliances with their `manufacturerName`, `modelName`, `typeLabel`, `functionLabel` and `codeValue` -```sql - -``` -> [!NOTE|label:Result] -> - +---------- # Test constraints -#### 1) Try to insert a record in a table using an existing primary key. +### Test 1 +Try to insert a record in a table using an existing primary key. ```sql INSERT INTO `Code`(`codeId`, `codeValue`) VALUES (1, 42) @@ -310,7 +333,10 @@ VALUES (1, 42) > [!NOTE|label:Result] > #1062 - Duplicate entry '1' for key 'Code.PRIMARY' -#### 2) Choose a table with at least a foreign key. Try to insert a record in that table, with the foreign key pointing to a non-existent record. +---------- + +### Test 2 +Choose a table with at least a foreign key. Try to insert a record in that table, with the foreign key pointing to a non-existent record. ```sql INSERT INTO `Model`(`modelId`, `manufacturerID`, `typeID`, `modelName`) VALUES (7, 1, 42, 'dummy test') @@ -318,7 +344,10 @@ VALUES (7, 1, 42, 'dummy test') > [!NOTE|label:Result] > #1452 - Cannot add or update a child row: a foreign key constraint fails (`sdi04`.`Model`, CONSTRAINT `Model_ibfk_2` FOREIGN KEY (`typeID`) REFERENCES `Type` (`typeID`) ON DELETE RESTRICT ON UPDATE RESTRICT) -#### 3) Try to delete the record with name “`HEVs`” in the table `Manufacturer`. Explain why this operation fails. +---------- + +### Test 3 +Try to delete the record with name “`HEVs`” in the table `Manufacturer`. Explain why this operation fails. ```sql DELETE FROM `Manufacturer` WHERE `Manufacturer`.`manufacturerName` like 'HEVs' @@ -326,7 +355,10 @@ WHERE `Manufacturer`.`manufacturerName` like 'HEVs' > [!NOTE|label:Result] > #1451 - Cannot delete or update a parent row: a foreign key constraint fails (`sdi04`.`Model`, CONSTRAINT `Model_ibfk_1` FOREIGN KEY (`manufacturerID`) REFERENCES `Manufacturer` (`manufacturerID`) ON DELETE RESTRICT ON UPDATE RESTRICT) -#### 4) Modify the foreign key definition in `Model` so that “`HEVs`” entry in `Manufacturer` can be deleted. The foreign key `manufacturerID` value in `Model` should be set to `NULL`. Test that it works as expected. +---------- + +### Test 4 +Modify the foreign key definition in `Model` so that “`HEVs`” entry in `Manufacturer` can be deleted. The foreign key `manufacturerID` value in `Model` should be set to `NULL`. Test that it works as expected. ```sql ALTER TABLE `Model` CHANGE `manufacturerID` `manufacturerID` INT NULL; @@ -342,7 +374,10 @@ WHERE `Manufacturer`.`manufacturerName` like 'HEVs' > [!NOTE|label:Result] > 1 row deleted -#### 5) We want now to delete all `Model` entries somehow related to a manufacturer when the latter is deleted from `Manufacturer`. To implement this feature, we should add a constraint `ON DELETE CASCADE` for the `manufacturerID` foreign key in `Model`. Try this and notice that this does not work. The reason is the following: you are not allowed to delete an entry in `Model` because a `FunctionList` refers to that entry. You could use `ON DELETE CASCADE` for all foreign keys, but deleting a single `Manufacturer` can trigger deletion of a good portion of the database! +---------- + +### Test 5 +We want now to delete all `Model` entries somehow related to a manufacturer when the latter is deleted from `Manufacturer`. To implement this feature, we should add a constraint `ON DELETE CASCADE` for the `manufacturerID` foreign key in `Model`. Try this and notice that this does not work. The reason is the following: you are not allowed to delete an entry in `Model` because a `FunctionList` refers to that entry. You could use `ON DELETE CASCADE` for all foreign keys, but deleting a single `Manufacturer` can trigger deletion of a good portion of the database! ```sql ALTER TABLE `Model` DROP FOREIGN KEY `Model_ibfk_1`; @@ -363,3 +398,5 @@ WHERE `Manufacturer`.`manufacturerName` like 'Onkyo' ``` > [!NOTE|label:Result] > 1 row deleted + +---------- \ No newline at end of file