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Quick TrainerSQL Keywords and Clauses
Learn what core SQL keywords and clauses do for querying and managing relational databases.
Code39 items3 levelsDifficulty 2/5
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Levels
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1
Basics
10 items
2
Filtering & Joining
19 items
3
Advanced
10 items
All 39 cards
SELECT
Retrieve data from a table
FROM
Specify the source table
WHERE
Filter rows by condition
INSERT INTO
Add new rows
UPDATE
Modify existing rows
DELETE
Remove rows
VALUES
Provide data for an insert
ORDER BY
Sort the result set
DISTINCT
Return only unique values
AS
Rename a column or table (alias)
LIMIT
Restrict the number of rows returned
GROUP BY
Group rows for aggregation
HAVING
Filter groups after aggregation
JOIN
Combine rows from multiple tables
INNER JOIN
Return only matching rows from both tables
LEFT JOIN
Keep all left-table rows plus matches
RIGHT JOIN
Keep all right-table rows plus matches
ON
Specify the join condition
AND
Require all conditions to be true
OR
Require at least one condition to be true
IN
Match a value against a list
BETWEEN
Match a value within a range
LIKE
Match a text pattern
IS NULL
Test for missing values
COUNT
Count the number of rows
SUM
Add up numeric values
AVG
Calculate the average of values
MIN
Find the smallest value
MAX
Find the largest value
CREATE TABLE
Define a new table
ALTER TABLE
Modify a table's structure
DROP TABLE
Delete a table entirely
PRIMARY KEY
Uniquely identify each row
FOREIGN KEY
Reference another table's key
INDEX
Speed up data lookups
UNION
Combine results of two queries (removing duplicates)
CASE
Return conditional values
WITH
Define a common table expression (CTE)
OVER
Define a window for window functions
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