diff --git a/backend/mysql/simple-crud.md b/backend/mysql/simple-crud.md
new file mode 100644
index 0000000..8c8b3e5
--- /dev/null
+++ b/backend/mysql/simple-crud.md
@@ -0,0 +1,444 @@
+# Mysql Simple CRUD Sheet Cheat
+
+## Sumário
+- [`SELECT`](#select)
+    - [`DISTINCT`](#DISTINCT)
+    - [`LIMIT` e `OFFSET`](#limit-e-offset)
+    - [`ORDER BY`](#order-by)
+    - [`COUNT`](#count)
+- [`WHERE`](#WHERE)
+    - [Condições](#Condições)
+    - [Operadores Matemáticos](#Operadores-Matemáticos)
+    - [Operadores Lógicos](#Operadores-Lógicos)
+    - [`IS`](#IS)
+    - [`NOT`](#NOT)
+    - [`LIKE`](#LIKE)
+    - [`BETWEEN`](#BETWEEN)
+    - [`IN`](#IN)
+- [Datas](#Datas)
+- [`INSERT`](#INSERT)
+- [`UPDATE`](#UPDATE)
+- [`DELETE`](#DELETE)
+
+
+## `SELECT`
+
+**Template**
+
+```sql
+SELECT
+    [DISTINCT]
+    expressão_de_coluna [, expressão_de_coluna] ...
+    [FROM <nome-da-tabela>]
+    [WHERE condição]
+    [ORDER BY expressão_de_coluna [ASC | DESC]]
+    [LIMIT contagem_de_linhas [OFFSET linha_puladas]]
+```
+> a sintaxe dos colchetes (`[]`) são declarações opcionais 
+
+> sintaxe `expressão [, expressão] ...;` representa que uma expressão é obrigatória, mas pode-se encadear mais expressões separadas por vírgula
+
+
+---
+
+```sql
+SELECT * FROM <nome-do-banco>.<nome-da-tabela>;
+SELECT <campo1>, <campo2> FROM <nome-do-banco>.<nome-da-tabela>;
+```
+
+**Exemplo**
+
+
+```sql
+SELECT * FROM sakila.actor;
+SELECT first_name, last_name FROM sakila.actor;
+```
+
+---
+
+### `DISTINCT`
+
+**Template**
+
+```sql
+SELECT DISTINCT <campo1> FROM <nome-do-banco>.<nome-da-tabela>;
+SELECT DISTINCT <campo1>, <campo2> FROM <nome-do-banco>.<nome-da-tabela>;
+```
+
+**Exemplo**
+
+```sql
+SELECT DISTINCT first_name FROM sakila.actor;
+```
+
+```sql
+SELECT DISTINCT first_name, last_name FROM sakila.actor;
+```
+
+### `LIMIT` e `OFFSET`
+
+```sql
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> LIMIT 10;
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> OFFSET 10;
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> LIMIT 10 OFFSET 10;
+```
+
+**Exemplo**
+
+```sql
+SELECT * FROM sakila.actor LIMIT 10;
+SELECT * FROM sakila.actor OFFSET 10;
+SELECT * FROM sakila.actor LIMIT 10 OFFSET 10;
+```
+
+---
+
+### `ORDER BY` 
+
+**Template**
+
+```sql
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> ORDER BY <campo1> DESC; -- é ASC por padrão
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> ORDER BY <campo1> ASC, <campo2> DESC;
+```
+
+**Exemplo**
+
+```sql
+SELECT * FROM sakila.actor ORDER BY first_name DESC;
+SELECT * FROM sakila.actor ORDER BY first_name DESC, last_name ASC;
+SELECT * FROM sakila.payment ORDER BY payment_date ASC;
+SELECT * FROM sakila.payment ORDER BY amount DESC;
+```
+
+---
+### `COUNT`
+
+**Template**
+
+```sql
+SELECT COUNT([DISTINCT] coluna [, coluna] ...) FROM <nome-do-banco>.<nome-da-tabela>;
+```
+
+**Exemplo**
+
+```sql
+SELECT COUNT(*) FROM sakila.film;
+SELECT COUNT(DISTINCT first_name) FROM sakila.actor;
+SELECT COUNT(DISTINCT first_name, last_name) FROM sakila.actor;
+```
+
+---
+
+## `WHERE`
+
+**Template**
+
+```sql
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> WHERE condition;
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> WHERE true; -- todas as linhas
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> WHERE false; -- nenhuma linha
+```
+
+---
+
+### Condições
+
+| OPERADOR | DESCRIÇÃO | Exemplo 
+|:---:|:----------|:--|
+| =   | IGUAL | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> = 1;` |
+| >   | MAIOR QUE | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> > 1;` |
+| <   | MENOR QUE | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> < 10;`  |
+| >=  | MAIOR QUE OU IGUAL | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> >= 10;` |
+| <=  | MENOR QUE OU IGUAL  | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> <= 10;` |
+| <>  | DIFERENTE DE | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> <> 10;` |
+| AND | OPERADOR LÓGICO E | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> < 10 AND <nome-da-tabela>.coluna2 > 7;` |
+| OR  | OPERADOR LÓGICO OU | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> < 10 OR <nome-da-tabela>.coluna2 > 7 `|
+| NOT | NEGAÇÃO | `SELECT * from <nome-da-tabela> WHERE NOT <nome-da-tabela>.<coluna1>;` |
+| IS  | COMPARA COM VALORES BOOLEANOS (TRUE, FALSE, NULL) | `SELECT * from <nome-da-tabela> WHERE <nome-da-tabela>.<coluna1> IS NULL;` |
+
+---
+
+### Operadores Matemáticos
+
+**Exemplos**
+
+```sql
+SELECT * FROM sakila.payment WHERE id = 1;
+```
+
+```sql
+SELECT * FROM sakila.payment WHERE amount < 10;
+```
+
+```sql
+SELECT * FROM sakila.payment WHERE amount >= 0.99;
+```
+
+```sql
+SELECT * FROM sakila.language WHERE name <> 'English';
+```
+
+---
+
+### Operadores Lógicos
+
+**Exemplos**
+
+```sql
+SELECT * FROM sakila.payment
+WHERE amount = 0.99 AND staff_id = 2;
+```
+
+```sql
+SELECT * FROM sakila.payment
+WHERE amount = 0.99 OR amount = 2.99;
+```
+
+```sql
+SELECT * FROM sakila.payment
+WHERE amount = 0.99 OR amount = 2.99 AND staff_id = 2;
+```
+
+---
+
+### `IS`
+
+**Exemplo**
+
+```sql
+SELECT * FROM sakila.staff WHERE picture IS NULL;
+```
+
+---
+
+### `NOT`
+
+**Exemplos**
+
+```sql
+SELECT * FROM sakila.staff WHERE NOT address_id = 3;
+```
+
+```sql
+SELECT * FROM sakila.staff WHERE picture IS NOT NULL;
+```
+
+---
+
+### `LIKE`
+|Sinal| Descrição|
+| :--: | :-- |
+| `%` | O sinal de percentual, que pode representar zero, um ou múltiplos caracteres
+| `_`|  O underscore (às vezes chamado de underline, no Brasil), que representa um único caractere |
+
+**Template**
+
+```sql
+SELECT * FROM <nome-do-banco>.<nome-da-tabela> 
+    WHERE coluna LIKE '__string%';
+```
+
+**Exemplos**
+
+```sql
+SELECT * FROM sakila.film
+    WHERE title LIKE '%don';
+```
+
+```sql
+SELECT * FROM sakila.film
+    WHERE title LIKE 'plu%';
+```
+
+```sql
+SELECT * FROM sakila.film
+WHERE title LIKE '%plu%';
+```
+
+```sql
+SELECT * FROM sakila.film
+    WHERE title LIKE 'p%r';
+```
+
+```sql
+SELECT * FROM sakila.film
+    WHERE title LIKE '_C%';
+```
+
+```sql
+SELECT * FROM sakila.film
+    WHERE title LIKE '________';
+```
+
+---
+
+### `BETWEEN`
+
+**Exemplos**
+
+```sql
+SELECT title, length FROM sakila.film
+    WHERE length BETWEEN 50 AND 120;
+```
+
+```sql
+SELECT rental_id, rental_date FROM sakila.rental
+    WHERE rental_date
+        BETWEEN '2005-05-27' AND '2005-07-17';
+```
+
+---
+
+### `IN`
+
+**Exemplos**
+
+```sql
+SELECT * FROM sakila.actor
+    WHERE first_name IN ('PENELOPE','NICK','ED','JENNIFER');
+```
+
+```sql
+SELECT * FROM sakila.actor
+    WHERE id IN (1, 2, 3, 7, 48, 42);
+```
+
+---
+
+## `Datas`
+
+**Exemplos**
+
+```sql
+SELECT DATE(payment_date) FROM sakila.payment; -- YYYY-MM-DD
+SELECT YEAR(payment_date) FROM sakila.payment; -- Ano
+SELECT MONTH(payment_date) FROM sakila.payment; -- Mês
+SELECT DAY(payment_date) FROM sakila.payment; -- Dia
+SELECT HOUR(payment_date) FROM sakila.payment; -- Hora
+SELECT MINUTE(payment_date) FROM sakila.payment; -- Minuto
+SELECT SECOND(payment_date) FROM sakila.payment; -- Segundo
+```
+
+```sql
+SELECT * FROM sakila.payment 
+    WHERE YEAR(payment_date) = 2006;
+```
+```sql
+SELECT * FROM sakila.payment
+    WHERE payment_date LIKE '2005-07-31%';
+```
+```sql
+SELECT * FROM sakila.payment
+    WHERE payment_date 
+        BETWEEN '2005-05-26 00:00:00' AND '2005-05-27 23:59:59';
+```
+```sql
+SELECT * FROM sakila.payment 
+    WHERE HOUR(payment_date) BETWEEN 10 AND 20;
+```
+
+---
+
+## `INSERT`
+
+**Template**
+
+```sql
+INSERT [IGNORE]
+    [INTO] <nome-da-tabela>
+    [(coluna [, coluna] ...)]
+    VALUES  (lista_de_valores) [, (lista_de_valores)] ... 
+
+lista_de_valores:
+    valor [, valor] ...
+```
+
+**Exemplos**
+
+```sql
+INSERT INTO sakila.actor (first_name, last_name)
+    VALUES ('Bell', 'Hooks');
+```
+```sql
+INSERT INTO sakila.actor (first_name, last_name)
+    VALUES ('Bell', 'Hooks'), ('Simone', 'Beauvoir');
+```
+
+---
+
+## `UPDATE`
+
+**Template**
+
+```sql
+UPDATE [IGNORE] <nome-do-banco>.<nome-da-tabela>
+    SET lista_de_atribuições 
+    [WHERE condição]
+    [ORDER BY ...]
+    [LIMIT contagem_de_linhas]
+
+lista_de_atribuições:
+    atribuição [, atribuição] ...
+
+atribuição:
+    coluna = valor
+```
+<!--     - UPDATE <nome-do-banco_de_dados>.<nome-da-tabela>
+    SET <campo1> = valor1, <campo2> = valor2 — (…) 
+    WHERE condição; -->
+
+**Exemplos**
+
+```sql
+UPDATE sakila.actor
+    SET last_name = 'Bauman'
+    WHERE first_name = 'ZERO';
+```
+
+```sql
+UPDATE sakila.staff
+    SET first_name = 'Jean-Paul', last_name = 'Sartre'
+    WHERE first_name = 'Mike';
+```
+
+⚠️ Caso seja necessário fazer um `UPDATE` sem `WHERE`:
+
+```sql
+SET SQL_SAFE_UPDATES = 0;
+```
+
+```sql
+UPDATE sakila.actor
+    SET first_name = 'Nina', last_name = 'Simone';
+```
+
+## `DELETE`
+
+**Template**
+
+```sql
+DELETE [IGNORE] FROM <nome-da-tabela> 
+    [WHERE condição]
+    [ORDER BY ...]
+    [LIMIT contagem_de_linhas]
+```
+
+**Exemplos**
+
+```sql
+DELETE FROM sakila.actor
+    WHERE first_name = 'NICK';
+```
+
+
+⚠️ Caso seja necessário fazer um `DELETE` sem `WHERE`:
+
+```sql
+SET SQL_SAFE_UPDATES = 0;
+```
+
+```sql
+DELETE FROM sakila.staff;
+```
+