Data Manipulation Language (DML) is a subset of SQL that is used to interact with data stored within a database. DML commands allow users to perform tasks like inserting new data, updating existing data, and deleting data. DML is essential for managing the data in relational databases, enabling efficient data handling and retrieval.
The main DML commands in SQL are INSERT, UPDATE, DELETE, and SELECT. Each command serves a specific function for manipulating data:
The INSERT command is used to add new rows to a table. It allows you to specify the values for each column in a new record.
sqlINSERT INTO table_name (column1, column2, ...) VALUES (value1, value2, ...);
Here:
The UPDATE command modifies existing records within a table based on specified conditions.
sqlUPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition;
Here:
The DELETE command removes records from a table. A condition can be specified to delete specific rows; otherwise, all rows will be deleted if no condition is provided.
sqlDELETE FROM table_name WHERE condition;
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The SELECT command retrieves data from one or more tables. It can specify particular columns, conditions, sorting, and grouping to refine the data fetched.
sqlSELECT column1, column2, ... FROM table_name WHERE condition;
Here:
DML commands provide a mechanism for interacting with data dynamically. DML allows users to manage, update, and access information effectively. These commands are commonly used in applications, reports, and systems where data must be modified frequently and reliably.
Data Manipulation Language (DML) is crucial in SQL for handling data stored in relational databases. Commands like INSERT, UPDATE, DELETE, and SELECT enable users to add, modify, remove, and retrieve data as needed. Understanding DML commands is essential for anyone working with databases to maintain data accuracy, consistency, and accessibility.
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