CREATE DATABASE IF NOT EXISTS database_name
DROP DATABASE IF EXISTS database_name
CREATE TABLE IF NOT EXISTS table_name (
column_a Datatype Constraints,
column_b Datatype Constraints,
);
| Datatype |
Description |
INT(n) |
Integer values |
FLOAT(n, d) |
Decimal values |
VARCHAR(n) |
String with max number of characters |
TEXT |
String with without set limit (max value of 65,535) |
DATE('YYYY-MM-DD') |
Year, month, and day |
DATETIME('YYYY-MM-DD HH:MI:SS') |
Year, month, day, hour, minute, and second |
TIMESTAMP('YYYY-MM-DD HH:MI:SS') |
Datetime corresponding to UNIX epoch time |
| Constraint |
Description |
PRIMARY KEY |
Unique identifier |
AUTO_INCREMENT |
Integer value is automatically added and incremented |
UNIQUE |
Value must be unique |
NOT NULL |
Value cannot be NULL |
DEFAULT |
Initialized with default value |
ALTER TABLE table_a
ADD column_a DataType
ALTER COLUMN column_a DataType
DROP column_a
RENAME TO table_b
DROP TABLE IF EXISTS table_name
SELECT *, column_a, column_b, AggregateFunction(column_a)
AS Alias
FROM table_a
JOIN table_b
ON table_a.column_a = table_b.column_a
WHERE Condition
AND Condition
OR Condition
NOT Condition
GROUP BY column_a
HAVING Condition
ORDER BY column_a
ASC
DESC
LIMIT Count
OFFSET Count
SELECT DISTINCT column_name
FROM table_name
| Join |
Description |
(INNER) JOIN |
Returns only matches from both tables |
LEFT JOIN |
Returns all entries from left table, and matches from right table |
RIGHT JOIN |
Returns all entries from right table, and matches from left table |
FULL JOIN |
Returns all entries from both tables |
| Function |
Description |
COUNT(column) |
Counts number of rows |
SUM(column) |
Adds all values |
MIN(column) |
Find the smallest value |
MAX(column) |
Find the largest value |
AVG(column) |
Find the average value |
| Operator |
Condition |
=, != |
Equal, not equal |
<, >, |
Less than, greater than |
<=, >= |
Less/greater than or equal to |
BETWEEN ... AND ... |
Within range of two values |
NOT BETWEEN ... AND ... |
Not within range of two values |
IN (...) |
Exists in list |
NOT IN (...) |
Does not exist in list |
LIKE |
Case insensitive equality comparison |
NOT LIKE |
Case insensitive inequality comparison |
% |
Matches a sequence of characters |
\_ |
Matches a single character |
IS NULL |
Value is null |
IS NOT NULL |
Value is not null |
ANY (...) |
If any values meet condition |
ALL |
If all values meet condition |
EXISTS |
If one or more records exist |
INSERT INTO table_name (column_a, column_b)
VALUES ("value_1", "value_2")
UPDATE table_name
SET column_a = "value_1"
column_b = "value_2"
WHERE Condition
DELETE FROM table_name
WHERE Condition