Cursusinhoud
Introduction to SQL
Introduction to SQL
2. Filtering Data
The WHERE ClauseChallenge: Help a Reader Find Their Favorite GenreChallenge: Fetching Older BooksConditional Expressions: Comparison OperatorsChallenge: Avoid the Damaged BooksChallenge: Highlight New ArrivalsChallenge: Budget-Friendly BooksConditional Expressions: The AND OperatorChallenge: Find Specific Books for a ReaderChallenge: Defining RangesChallenge: Multiple ConditionsConditional Expressions: The OR OperatorChallenge: Matching Multiple OptionsChallenge: Excluding A RangeConditional Expressions: The NOT OperatorChallenge: Negating a Range
3. Sorting Data
Basic SortingChallenge: Sorting the Library CatalogueSorting by Multiple ColumnsChallenge: Further Sorting the CatalogueSorting after Filtering DataChallenge: Find the Cheapest BooksChallenge: Help a Customer Find a BookThe LIMIT KeywordChallenge: Select Books for the Collector's SectionChallenge: Affordable Books
4. Populating a Database
Creating a TableChallenge: Creating a new Books TableInserting Rows into a TableChallenge: Inserting DataChallenge: Inserting More DataInserting Multiple RowsChallenge: Inserting Bulk DataPrimary KeysThe SERIAL KeywordChallenge: Changing the Books StructureSpecifying Default ValuesChallenge: Further Improving the Books Table
5. Updating & Deleting Data
Primary Keys
A primary key is a column in a table which:
- Has a unique value for each row (no duplicate values);
- Cannot contain an
empty/nullvalue for any row.
A column can be marked as a primary key using the PRIMARY KEY keyword, inside the CREATE statement while creating the respective table.
Demonstration:
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Sectie 4. Hoofdstuk 8
