رتبها

Mastering SQL!
A Thread 🐦 with 20 Crucial SQL Commands with Explanations 👇

SELECT 📥 Select data from a database table. It retrieves rows that match specified conditions.
Example:
"SELECT column1, column2 FROM table_name WHERE condition;"

INSERT 📤 Add new rows to a table.
Use "INSERT INTO table_name (column1, column2) VALUES (value1, value2);" to add data.

UPDATE 🔧 Modify existing data in a table.
Syntax:
"UPDATE table_name SET column1 = value1, column2 = value2 WHERE condition;"

DELETE 🗑️ Remove specific rows from a table.
Usage:
"DELETE FROM table_name WHERE condition;"

WHERE ❓ Filter records based on specified conditions. It follows the SELECT, UPDATE, or DELETE statement.
Example:
"SELECT * FROM table_name WHERE condition;"

ORDER BY 📊 Sort query results in ascending or descending order.
Syntax:
"SELECT column1, column2 FROM table_name ORDER BY column1 ASC;"

GROUP BY 👥 Group rows with identical values in specified columns. Useful with aggregate functions like COUNT, SUM, etc.
Format:
"SELECT column1, COUNT(*) FROM table_name GROUP BY column1;"

JOIN ➕ Combine data from two or more tables based on a related column.
Common types: INNER, LEFT, RIGHT, FULL.
Example:
"SELECT * FROM table1 INNER JOIN table2 ON table1.column = table2.column;"

LIKE 🎯 Perform partial string matching in WHERE clauses. Use "%" as a wildcard.
Example:
"SELECT * FROM table_name WHERE column LIKE 'keyword%';"

IN ✔️ Check if a value matches any value in a list.
Example:
"SELECT * FROM table_name WHERE column IN (value1, value2, value3);"

BETWEEN 🌈 Retrieve values within a specified range.
Format:
"SELECT * FROM table_name WHERE column BETWEEN value1 AND value2;"

NULL 🚫 Identify NULL values in the database.
Use "IS NULL" or "IS NOT NULL" in WHERE clauses.

DISTINCT 🧊 Fetch unique values from a specific column.
Syntax:
"SELECT DISTINCT column FROM table_name;"

HAVING 🕵️ Filter groups based on aggregate function results.
Example:
"SELECT column1, COUNT() FROM table_name GROUP BY column1 HAVING COUNT() > 5;"

AS 🎭 Alias column names or table names. Improve readability.
Example:
"SELECT column1 AS alias_name FROM table_name;"

UNION 🤝 Merge the results of multiple SELECT queries into a single result set.
Use "UNION" or "UNION ALL" to include duplicates.

CREATE TABLE 🗄️ Create a new database table.
Syntax:
"CREATE TABLE table_name (column1 datatype, column2 datatype, ...);"

ALTER TABLE 🔧 Modify an existing table structure.
For example, add new columns or change data types.
Syntax:
"ALTER TABLE table_name ADD column_name datatype;"

DROP TABLE 💥 Delete a table and its data from the database. Use with caution!
Syntax:
"DROP TABLE table_name;"

TRUNCATE TABLE 🗑️ Remove all rows from a table without deleting the table structure.
Use "TRUNCATE TABLE table_name;" for quick deletion.

Time for Bonus 💰💰

COUNT 📈 COUNT is an aggregate function that counts the number of rows matching the specified condition.
Example:
"SELECT COUNT(*) FROM table_name WHERE condition;"

AVG 🧮 AVG calculates the average value of a numeric column.
Usage:
"SELECT AVG(column) FROM table_name;"

MAX ⬆️ MAX returns the maximum value from a column. It is used to find the highest value in a specific column.
Example:
"SELECT MAX(column) FROM table_name;"

MIN ⬇️ MIN returns the minimum value from a column. It helps find the lowest value in a specific column.
Syntax:
"SELECT MIN(column) FROM table_name;"

SUM ➕ SUM calculates the sum of values in a numeric column. It is used to get the total of a specific column.
Example:
"SELECT SUM(column) FROM table_name;"

Happy SQL-ing! 🚀📚 Keep mastering these commands to become a SQL pro!
If you need further assistance, feel free to ask! #SQL #Database #DataManipulation

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