SQL requests you need to know by heart

SQL is a standardized computer language used to operate relational databases. The data manipulation language part of SQL allows to find, add, modify or delete data in relational databases

RequestDescription
INSERT INTO table_name (column1, column2, column3, …)
VALUES (value1, value2, value3, …);
The INSERT INTO statement is used to insert new records in a table.
INSERT IGNORE INTO table_name (column1, column2, column3, …)
VALUES (value1, value2, value3, …);
The INSERT IGNORE INTO statement is used to insert new records in a table, without modifying the already existing records.
DELETE FROM table_name WHERE condition;The DELETE FROM  statement is used to delete existing records in a table, according to a given condition.
UPDATE table_name
SET column1 = value1, column2 = value2
WHERE condition;
The UPDATE statement is used to modify the existing records in a table, according to a given condition.
SELECT column1, column2, …
FROM table_name
ORDER BY column1 ASC;
The ORDER BY keyword sorts the records in ascending  ASC order by default. To sort the records in descending order, use the DESC keyword.
DROP DATABASE myDataBase;The DROP DATABASE request is used to delete a database. Be careful while using it.
DROP TABLE my_table;The DROP TABLE request is used to delete a table, without looking if there is data in it. Be careful while using it.
CREATE TABLE Shnapshnoot (
    ID int NOT NULL,
    Username varchar(255) NOT NULL,
    password varchar(255),
    Age int,
    PRIMARY KEY (ID)
);
The CREATE TABLE request is used to create a table in a database. The PRIMARY KEY keyword uniquely identifies each record in a table. Primary keys must contain UNIQUE values, and can not contain NULL values. Each tables can have only ONE primary key.

SELECT COUNT(*)
FROM table_name
WHERE condition;
The COUNT() function returns the number of rows that matches your given condition.

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