| Command |
Syntax |
Description |
| ALTER table |
ALTER TABLE table_name ADD column_name datatype; |
It is used to add columns to a table in a database |
| AND |
SELECT column_name(s)FROM table_nameWHERE column_1 = value_1 AND column_2 = value_2; |
It is an operator that is used to combine two conditions |
| AS |
SELECT column_name AS ‘Alias’FROM table_name; |
It is a keyword in SQL that is used to rename a column or table using an alias name |
| AVG |
SELECT AVG(column_name)FROM table_name; |
It is used to aggregate a numeric column and return its average |
| SQL BETWEEN |
SELECT column_name(s)FROM table_nameWHERE column_name BETWEEN value_1 AND value_2; |
It is an operation used to filter the result within a certain range |
| CASE |
SELECT column_name,CASEWHEN condition THEN ‘Result_1’WHEN condition THEN ‘Result_2’ELSE ‘Result_3’ENDFROM table_name; |
It is a statement used to create different outputs inside a SELECT statement |
| COUNT |
SELECT COUNT(column_name)FROM table_name; |
It is a function that takes the name of a column as an argument and counts the number of rows when the column is not NULL |
| Create TABLE |
CREATE TABLE table_name ( column_1 datatype, column_2 datatype, column_3 datatype); |
It is used to create a new table in a database and specify the name of the table and columns inside it |
| DELETE |
DELETE FROM table_nameWHERE some_column = some_value; |
It is used to remove the rows from a table |
| GROUP BY |
SELECT column_name, COUNT(*)FROM table_nameGROUP BY column_name; |
It is a clause in SQL used for aggregate functions in collaboration with the SELECT statement |
| HAVING |
SELECT column_name, COUNT(*)FROM table_nameGROUP BY column_nameHAVING COUNT(*) > value; |
It is used in SQL because the WHERE keyword cannot be used in aggregating functions |
| INNER JOIN |
SELECT column_name(s)FROM table_1JOIN table_2 ON table_1.column_name = table_2.column_name; |
It is used to combine rows from different tables if the Join condition goes TRUE |
| INSERT |
INSERT INTO table_name (column_1, column_2, column_3) VALUES (value_1, ‘value_2’, value_3); |
It is used to add new rows to a table |
| IS NULL/ IS NOT NULL |
SELECT column_name(s)FROM table_nameWHERE column_name IS NULL; |
It is an operator used with the WHERE clause to check for the empty values |
| LIKE |
SELECT column_name(s)FROM table_nameWHERE column_name LIKE pattern; |
It is a special operator used with the WHERE clause to search for a specific pattern in a column |
| LIMIT |
SELECT column_name(s)FROM table_nameLIMIT number; |
It is a clause to specify the maximum number of rows the result set must have |
| MAX |
SELECT MAX(column_name)FROM table_name; |
It is a function that takes a number of columns as an argument and returns the largest value among them |
| MIN |
SELECT MIN(column_name)FROM table_name; |
It is a function that takes a number of columns as an argument and returns the smallest value among them |
| OR |
SELECT column_nameFROM table_nameWHERE column_name = value_1 OR column_name = value_2; |
It is an operator that is used to filter the result set to contain only the rows where either condition is TRUE |
| ORDER BY |
SELECT column_nameFROM table_nameORDER BY column_name ASC | DESC; |
It is a clause used to sort the result set by a particular column either numerically or alphabetically |
| OUTER JOIN |
SELECT column_name(s)FROM table_1LEFT JOIN table_2 ON table_1.column_name = table_2.column_name; |
It issued to combine rows from different tables even if the condition is NOT TRUE |
| ROUND |
SELECT ROUND(column_name, integer)FROM table_name; |
It is a function that takes the column name and an integer as an argument and rounds the values in a column to the number of decimal places specified by an integer |
| SELECT |
SELECT column_name FROM table_name; |
It is a statement that is used to fetch data from a database |
| SELECT DISTINCT |
SELECT DISTINCT column_nameFROM table_name; |
It is used to specify that the statement is a query that returns unique values in specified columns |
| SUM |
SELECT SUM(column_name)FROM table_name; |
It is a function used to return the sum of values from a particular column |
| UPDATE |
UPDATE table_nameSET some_column = some_valueWHERE some_column = some_value; |
It is used to edit rows in a table |
| WHERE |
SELECT column_name(s)FROM table_nameWHERE column_name operator value; |
It is a clause used to filter the result set to include the rows where the condition is TRUE |
| WITH |
WITH temporary_name AS (SELECT *FROM table_name)SELECT *FROM temporary_nameWHERE column_name operator value; |
It is used to store the result of a particular query in a temporary table using an alias |