modified MySQL.md"

1 files changed, 57 insertions, 53 deletions

diff --git a/SI/Resource/Data Science/SQL/MySQL/MySQL.md b/SI/Resource/Data Science/SQL/MySQL/MySQL.md
index 5990a20..c9567f9 100644
--- a/SI/Resource/Data Science/SQL/MySQL/MySQL.md
+++ b/SI/Resource/Data Science/SQL/MySQL/MySQL.md
@@ -10,7 +10,7 @@ tags:
   - SQL
 ---
 
-# [[MySQL]]
+# MySQL
 
 ## Variables
 
@@ -23,9 +23,7 @@ DATE -- YYYY-MM-DD
 TIMESTAMP -- YYYY-MM-DD HH:MM:SS
 ```
 
-## Basic
-
-### Table
+## Table
 
 - View tables
 
@@ -33,6 +31,16 @@ TIMESTAMP -- YYYY-MM-DD HH:MM:SS
 .tables -- sqlite
 ```
 
+- Describe tables
+
+```sql
+DESCRIBE table_name;
+
+DESC table_name;
+```
+
+## DDL (Data Definition Language) - CREATE, ALTER, DROP, TRUNCATE
+
 - Create tables
 
 ```sql
@@ -51,61 +59,53 @@ CREATE TABLE table_name (
 DROP TABLE table_name;
 ```
 
-- Describe tables
+- ALTER columns
 
 ```sql
-DESCRIBE table_name;
+ALTER TABLE table_name ADD column_name DECIMAL(3,2);
 
-DESC table_name;
+ALTER TABLE table_name DROP COLUMN column_name;
 ```
 
-- RENAME table
+- ALTER ... RENAME table
 
 ```sql
 ALTER TABLE table_name
 RENAME TO new_table_name;
 ```
 
-- UPDATE table
-
-```sql
-UPDATE table_name
-SET 1_column_name = new_value, (2_column_name = new_value);
-(WHERE other_column_name = value;)
-```
-
-### Column
-
-- ALTER columns
-
-```sql
-ALTER TABLE table_name ADD column_name DECIMAL(3,2);
-
-ALTER TABLE table_name DROP COLUMN column_name;
-```
-
-- ADD column
+- ALTER ... ADD column
 
 ```sql
 ALTER TABLE table_name
 ADD COLUMN new_column_name DATA_TYPE;
 ```
 
-- CHANGE column_name
+- ALTER CHANGE column_name
 
 ```sql
 ALTER TABLE table_name
 CHANGE COLUMN column_name (DATA_TYPE);
 ```
 
-- DROP column_name
+- ALTER DROP column_name
 
 ```sql
 ALTER TABLE table_name
 DROP COLUMN column_name;
 ```
 
-### Data
+## DML (Data Manipulation Language): UPDATE commands (UPDATE, INSERT, DELETE) & Query command (SELECT)
+
+### UPDATE commands
+
+- UPDATE table
+
+```sql
+UPDATE table_name
+SET 1_column_name = new_value, (2_column_name = new_value);
+(WHERE other_column_name = value;)
+```
 
 - INSERT INTO data
 
@@ -115,7 +115,16 @@ INSERT INTO table_name VALUES(data);
 INSERT INTO table_name(column_name) VALUES(data);
 ```
 
-- SELECT \*/data
+- DELETE FROM data
+
+```sql
+DELETE FROM table_name;
+WHERE a_column_name = value;
+```
+
+### Query command
+
+- SELECT data
 
 ```sql
 SELECT *
@@ -125,14 +134,9 @@ SELECT column_name (AS col_name)
 FROM table_name;
 ```
 
-- DELETE FROM data
-
-```sql
-DELETE FROM table_name;
-WHERE a_column_name = value;
-```
+#### FROM clause
 
-### Condition
+##### Condition
 
 - ORDER BY ... ASCending & DESCending
 
@@ -184,7 +188,7 @@ FROM table_name;
 WHERE column_name BETWEEN int AND int;
 ```
 
-#### Filtering
+###### Filtering
 
 - LIKE (target: char%, %char, %str%, _char%, char_%\_%, char%char)
 
@@ -205,7 +209,7 @@ SELECT *
 FROM table_name;
 ```
 
-## Functions
+#### Functions
 
 - Calculation (fn: SUM(), COUNT(), MIN(), MAX(), AVG())
 
@@ -249,7 +253,7 @@ SELECT CONCAT(str_1, str_2, ...)
 FROM table_name;
 ```
 
-### Date
+##### Date
 
 - Date & Time (fn: CURDATE(), CURTIME(), NOW(), YEAR(), MONTH(), DAY(), LAST_DAY(), WEEKDAY(), DAYNAME())
 
@@ -266,7 +270,7 @@ SELECT column_name
 FROM table_name;
 ```
 
-#### Date Format
+###### Date Format
 
 - DATE_FORMAT (fm: %Y, %y, %M, %b, %W, %a, %i, %T, %m, %c, %d, %e, %I, %H, %r, %S)
 
@@ -275,7 +279,7 @@ SELECT column_name, DATE_FORMAT(column_name, fm_1, fm_2, ...)
 FROM table_name;
 ```
 
-## GROUP BY
+#### GROUP BY
 
 - GROUP BY column_name_1, column_name_2, ..., Calculation_1, Calculation_2, ...
 
@@ -294,7 +298,7 @@ GROUP BY column_name;
 HAVING condition;
 ```
 
-## Division & Analysis
+#### Division & Analysis
 
 - RANK()/DENSE_RANK() OVER (ORDER BY column_name)
 
@@ -304,7 +308,7 @@ SELECT *
 FROM table_name;
 ```
 
-### Division
+##### Division
 
 - PARTITION BY
 
@@ -314,7 +318,7 @@ SELECT *
 FROM table_name
 ```
 
-### Before/After
+##### Before/After
 
 - LAG(column_name, int): before /LEAD(column_name, int): after
 
@@ -325,7 +329,7 @@ FROM table_nam e
 ORDER BY column_name
 ```
 
-### Border
+##### Border
 
 - ROWS (FRAME: CURRENT ROW, int PRECEDING, int FOLLOWING, UNBOUNDED PRECEDING, UNBOUNDED FOLLOWING) AND (FRAME)
 
@@ -347,7 +351,7 @@ FROM table_name;
 ORDER BY column_name_1, column_name_2;
 ```
 
-### Merge
+##### Merge
 
 - (INNER) JOIN
 
@@ -376,9 +380,9 @@ FROM table_name_1 CROSS
 	  (...)
 ```
 
-## Sub Query / Temporary Table
+#### Sub Query / Temporary Table
 
-### Multi Columns
+##### Multi Columns
 
 - ()
 
@@ -392,7 +396,7 @@ FROM
 (WHERE condition;)
 ```
 
-### Uni Column & Uni Data
+##### Uni Column & Uni Data
 
 - IN
 
@@ -413,7 +417,7 @@ WHERE condition =(/IN)
 		 FROM table_name_2;)
 ```
 
-### VIEW / WITH
+##### VIEW / WITH
 
 - Create
 
@@ -442,7 +446,7 @@ FROM table_name
 (WHERE condition)
 ```
 
-## Custom Function
+#### Custom Function
 
 - Nominal Return Value