SQL

18 Jan, 2022

1. Select ALL from a table

SELECT * FROM (table name);

2. Select certain columns from a table

SELECT column1, column2, column3 FROM table;

3. Select all the unique or distinct rows in a column from a table. Another way to think of it is "removing duplicates"

SELECT DISTINCT column FROM table;

4. Selecting colums with rows by implementing conditions.

SELECT (column name) FROM (table) WHERE (condition);

example of conditions:

a) Equal =

SELECT (column name) FROM (table name) WHERE (column name = cell data/value)

b) Greater than >

SELECT (column name) FROM (table name) WHERE (column name > value)

c) Less than <

SELECT (column name) FROM (table name) WHERE (column name < value)

d) Greater than or equal >=

SELECT (column name) FROM (table name) WHERE (column name >= value)

e) Less than or equal <=

SELECT (column name) FROM (table name) WHERE (column name <= value)

f) Not equal, or exception <>

SELECT (column name) FROM (table name) WHERE (column name <> cell data/value)

In some versions of SQL: !=

SELECT (column name) FROM (table name) WHERE (column name != cell data/value)

g) Between a certain range: BETWEEN

SELECT (column name) FROM (table name) WHERE (column name BETWEEN value1 AND value2)

h) Search for a pattern: LIKE

i) To specify multiple possible values for a column: IN