10.3.2 Data manipulation language (DML)

• What is the purpose of Data Manipulation Language (DML)?

  To manage data within tables
• The `SELECT` command in DML is used to retrieve
• The `INSERT` command is used to add new data to a table.
• What does the `UPDATE` command in DML do?

  Modifies existing data
• The `DELETE` command is used to remove data from a table
• DML allows users to retrieve, insert, update, and delete data.
• The `SELECT` command can retrieve data from multiple tables.
• The `INSERT` command requires specifying the table name and the values
• What clause is used with `UPDATE` to specify which rows to modify?

  WHERE
• Order the main DML commands based on their purpose:

  1️⃣ SELECT (Retrieve data)

  2️⃣ INSERT (Add new data)

  3️⃣ UPDATE (Modify existing data)

  4️⃣ DELETE (Remove data)
• The `INSERT` command can only add one row at a time.

  False
• The `UPDATE` command can modify multiple rows if the `WHERE` clause matches conditions
• What happens if the `WHERE` clause is omitted in a `DELETE` statement?

  All data is removed
• The `SELECT` command is used to add new data to a table.

  False
• DML is a subset of SQL
• What is the primary function of the `SELECT` command in DML?

  Retrieving data
• The `INSERT` statement requires specifying both column names and values.
• Provide an example of an `INSERT` statement to add a new student to the `Students` table.

  \begin{align * } \textbf{INSERT INTO} & \text{Students} \\ & (\text{StudentID}, \text{Name}, \text{Age}, \text{Major}) \\ \textbf{VALUES} & (789, '\text{Jane Doe}', 22, '\text{Economics}'); \end{align * }
• When using `INSERT`, the values must match the data types of the columns
• The `INSERT` statement in SQL is used to add new rows
• The number and order of values in an `INSERT` statement must match the column list.
• If some columns are omitted in an `INSERT` statement, they must allow NULL values or have default constraints
• What is the primary purpose of Data Manipulation Language (DML) in SQL?

  Manage data
• Match the DML command with its purpose:

  SELECT ↔️ Retrieves data

  INSERT ↔️ Adds new data

  UPDATE ↔️ Modifies existing data

  DELETE ↔️ Removes data
• The `SELECT` command in DML is used to retrieve data from one or more tables
• The `UPDATE` command in DML modifies existing data based on a `WHERE` clause.
• What is the primary purpose of the `DELETE` command in DML?

  Remove data
• The main commands in DML include `SELECT`, `INSERT`, `UPDATE`, and DELETE
• Steps for using the `INSERT` statement in SQL:

  1️⃣ Specify the table name

  2️⃣ List the column names

  3️⃣ Provide the values to insert

  4️⃣ Execute the statement
• What is the primary purpose of the `UPDATE` statement in SQL?

  Modify existing data
• The `DELETE` statement in SQL requires a `WHERE` clause to prevent unintentional data loss
• The `DELETE` statement in SQL is used to remove rows from a table based on specified conditions
• The `WHERE` clause is optional in a `DELETE` statement.

  False
• Data Manipulation Language (DML) is a subset of SQL that manages data
• Match the DML command with its purpose:

  SELECT ↔️ Retrieve data

  INSERT ↔️ Add new data

  UPDATE ↔️ Modify data

  DELETE ↔️ Remove data
• Using the `WHERE` clause in `UPDATE` and `DELETE` commands avoids unintentional data changes
• The `UPDATE` statement in SQL is used to modify existing data
• Steps to update data using the `UPDATE` statement:

  1️⃣ Identify the table

  2️⃣ Use the `SET` clause to specify changes

  3️⃣ Use the `WHERE` clause to filter rows
• The `DELETE` statement requires the `WHERE` clause to prevent unintentional data loss
• Match the `SELECT` statement example with its description:

  `SELECT * FROM Students;` ↔️ Select all columns

  `SELECT Name, Age FROM Students;` ↔️ Select specific columns

  `SELECT Name, Age FROM Students WHERE Major = 'Computer Science';` ↔️ Select with a condition