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Sam
Sam

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Tips On Working with data in sql

Working with data in SQL involves several operations such as inserting data, querying data, updating data, and deleting data. Here are some basic SQL commands for these operations:

1; Inserting Data

You can insert data into a table using the INSERT INTO statement. Here's an example:

INSERT INTO table_name (column1, column2, column3) VALUES (value1, value2, value3);
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2; Querying Data

You can retrieve data from a table using the SELECT statement. Here's an example:


SELECT column1, column2 FROM table_name WHERE condition;

You can also retrieve all columns with *:

SELECT * FROM table_name;
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3; Updating Data

You can update existing data in a table using the UPDATE statement. Here's an example:

UPDATE table_name

SET column1 = value1, column2 = value2

WHERE condition;
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4; Deleting Data

You can delete data from a table using the DELETE statement. Here's an example:

DELETE FROM table_name WHERE condition;
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Remember to replace table_name, column1, column2, value1, value2, and condition with your actual table name, column names, values, and condition.

Note: Be careful with the DELETE statement. If you omit the WHERE clause, it will remove all records from the table.

5; Joining Tables

You can join tables to combine rows from two or more tables based on a related column. Here's an example of an inner join:

SELECT column1, column2

FROM table1

INNER JOIN table2

ON table1.matching_column = table2.matching_column;

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Remember, SQL is a powerful language for managing and manipulating data in relational databases. The commands above are just the basics. There are many more advanced commands and features available in SQL.

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