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SELECT c1, c2
FROM t1
INNER JOIN t2 ON condition;
Inner join t1 and t2
SELECT c1, c2
FROM t1
LEFT JOIN t2 ON condition;
Left join t1 and t1
SELECT c1, c2
FROM t1
FULL OUTER JOIN t2 ON condition;
Perform full outer join
SELECT c1, c2
FROM t1
CROSS JOIN t2;
Produce a Cartesian product of rows in tables
SELECT c1, c2
FROM t1 A
INNER JOIN t2 B ON condition;
Join t1 to itself using INNER JOIN clause
SELECT c1, c2
FROM t1
RIGHT JOIN t2 ON condition;
Right join t1 and t2
SELECT c1, c2 FROM t;
Query data in columns c1, c2 from a table
SELECT * FROM t;
Query all rows and columns from a table
SELECT c1, c2 FROM t
WHERE condition;
Query data and filter rows with a condition
SELECT DISTINCT c1 FROM t
WHERE condition;
Query distinct rows from a table
SELECT c1, aggregate(c2)
FROM t
GROUP BY c1;
Group rows using an aggregate function
SELECT c1, aggregate(c2)
FROM t
GROUP BY c1
HAVING condition;
Filter groups using HAVING clause
SELECT c1, c2 FROM t
ORDER BY c1 ASC [DESC];
Sort the result set in ascending or descending
order
SELECT c1, c2 FROM t1
UNION [ALL]
SELECT c1, c2 FROM t2;
Combine rows from two queries
SELECT c1, c2 FROM t1
INTERSECT
SELECT c1, c2 FROM t2;
Return the intersection of two queries
SELECT c1, c2 FROM t1
MINUS
SELECT c1, c2 FROM t2;
Subtract a result set from another result set
SELECT c1, c2 FROM t1
WHERE c1 [NOT] LIKE pattern;
Query rows using pattern matching %, _
SELECT c1, c2 FROM t
WHERE c1 [NOT] IN value_list;
Query rows in a list
SELECT c1, c2 FROM t
WHERE c1 BETWEEN low AND high;
Query rows between two values
SELECT c1, c2 FROM t
WHERE c1 IS [NOT] NULL;
Check if values in a table is NULL or not
QUERYING DATA FROM A TABLE QUERYING FROM MULTIPLE TABLES USING SQL OPERATORS
SELECT c1, c2 FROM t
ORDER BY c1
LIMIT n OFFSET offset;
Skip offset of rows and return the next n rows
SELECT c1, c2
FROM t1, t2;
Another way to perform cross join
SQL CHEAT SHEET http://www.sqltutorial.org
CREATE TABLE t(
c1 INT, c2 INT, c3 VARCHAR,
PRIMARY KEY (c1,c2)
);
Set c1 and c2 as a primary key
CREATE TABLE t (
id INT PRIMARY KEY,
name VARCHAR NOT NULL,
price INT DEFAULT 0
);
Create a new table with three columns
INSERT INTO t(column_list)
VALUES(value_list);
Insert one row into a table
INSERT INTO t(column_list)
VALUES (value_list),
(value_list), ….;
Insert multiple rows into a table
INSERT INTO t1(column_list)
SELECT column_list
FROM t2;
Insert rows from t2 into t1
UPDATE t
SET c1 = new_value,
c2 = new_value
WHERE condition;
Update values in the column c1, c2 that match
the condition
DELETE FROM t;
Delete all data in a table
DELETE FROM t
WHERE condition;
Delete subset of rows in a table
DROP TABLE t ;
Delete the table from the database
ALTER TABLE t ADD column;
Add a new column to the table
ALTER TABLE t DROP COLUMN c ;
Drop column c from the table
CREATE TABLE t1(
c1 INT PRIMARY KEY,
c2 INT,
FOREIGN KEY (c2) REFERENCES t2(c2)
);
Set c2 column as a foreign key
CREATE TABLE t(
c1 INT, c1 INT,
UNIQUE(c2,c3)
);
Make the values in c1 and c2 unique
CREATE TABLE t(
c1 INT, c2 INT,
CHECK(c1> 0 AND c1 >= c2)
);
Ensure c1 > 0 and values in c1 >= c2
CREATE TABLE t(
c1 INT PRIMARY KEY,
c2 VARCHAR NOT NULL
);
Set values in c2 column not NULL
TRUNCATE TABLE t;
Remove all data in a table
UPDATE t
SET c1 = new_value;
Update new value in the column c1 for all rows
MANAGING TABLES USING SQL CONSTRAINTS MODIFYING DATA
ALTER TABLE t ADD constraint;
Add a constraint
Rename a table from t1 to t2
ALTER TABLE t DROP constraint;
Drop a constraint
ALTER TABLE t1 RENAME c1 TO c2 ;
Rename column c1 to c2
SQL CHEAT SHEET http://www.sqltutorial.org
CREATE INDEX idx_name
ON t(c1,c2);
Create an index on c1 and c2 of the table t
MANAGING INDEXES
CREATE VIEW v(c1,c2)
AS
SELECT c1, c2
FROM t;
Create a new view that consists of c1 and c2
MANAGING VIEWS MANAGING TRIGGERS
SQL CHEAT SHEET http://www.sqltutorial.org
DROP VIEW view_name
Delete a view
DROP INDEX idx_name;
Drop an index
CREATE VIEW v(c1,c2)
AS
SELECT c1, c2
FROM t;
WITH [CASCADED | LOCAL] CHECK OPTION;
Create a new view with check option
CREATE RECURSIVE VIEW v
AS
select-statement -- anchor part
UNION [ALL]
select-statement; -- recursive part
Create a recursive view
CREATE OR MODIFY TRIGGER trigger_name
WHEN EVENT
ON table_name TRIGGER_TYPE
EXECUTE stored_procedure;
Create or modify a trigger
DROP TRIGGER trigger_name
Delete a specific trigger
CREATE UNIQUE INDEX idx_name
ON t(c3,c4);
Create a unique index on c3, c4 of the table t
SQL AGGREGATE FUNCTIONS
AVG returns the average of a list
CREATE TEMPORARY VIEW v
AS
SELECT c1, c2
FROM t;
Create a temporary view
WHEN
• BEFORE – invoke before the event occurs
• AFTER – invoke after the event occurs
EVENT
• INSERT – invoke for INSERT
• UPDATE – invoke for UPDATE
• DELETE – invoke for DELETE
TRIGGER_TYPE
• FOR EACH ROW
• FOR EACH STATEMENT
CREATE TRIGGER before_insert_person
BEFORE INSERT
ON person FOR EACH ROW
EXECUTE stored_procedure;
Create a trigger invoked before a new row is
inserted into the person table
COUNT returns the number of elements of a list
SUM returns the total of a list
MAX returns the maximum value in a list
MIN returns the minimum value in a list

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Sql cheat sheet

  • 1. SELECT c1, c2 FROM t1 INNER JOIN t2 ON condition; Inner join t1 and t2 SELECT c1, c2 FROM t1 LEFT JOIN t2 ON condition; Left join t1 and t1 SELECT c1, c2 FROM t1 FULL OUTER JOIN t2 ON condition; Perform full outer join SELECT c1, c2 FROM t1 CROSS JOIN t2; Produce a Cartesian product of rows in tables SELECT c1, c2 FROM t1 A INNER JOIN t2 B ON condition; Join t1 to itself using INNER JOIN clause SELECT c1, c2 FROM t1 RIGHT JOIN t2 ON condition; Right join t1 and t2 SELECT c1, c2 FROM t; Query data in columns c1, c2 from a table SELECT * FROM t; Query all rows and columns from a table SELECT c1, c2 FROM t WHERE condition; Query data and filter rows with a condition SELECT DISTINCT c1 FROM t WHERE condition; Query distinct rows from a table SELECT c1, aggregate(c2) FROM t GROUP BY c1; Group rows using an aggregate function SELECT c1, aggregate(c2) FROM t GROUP BY c1 HAVING condition; Filter groups using HAVING clause SELECT c1, c2 FROM t ORDER BY c1 ASC [DESC]; Sort the result set in ascending or descending order SELECT c1, c2 FROM t1 UNION [ALL] SELECT c1, c2 FROM t2; Combine rows from two queries SELECT c1, c2 FROM t1 INTERSECT SELECT c1, c2 FROM t2; Return the intersection of two queries SELECT c1, c2 FROM t1 MINUS SELECT c1, c2 FROM t2; Subtract a result set from another result set SELECT c1, c2 FROM t1 WHERE c1 [NOT] LIKE pattern; Query rows using pattern matching %, _ SELECT c1, c2 FROM t WHERE c1 [NOT] IN value_list; Query rows in a list SELECT c1, c2 FROM t WHERE c1 BETWEEN low AND high; Query rows between two values SELECT c1, c2 FROM t WHERE c1 IS [NOT] NULL; Check if values in a table is NULL or not QUERYING DATA FROM A TABLE QUERYING FROM MULTIPLE TABLES USING SQL OPERATORS SELECT c1, c2 FROM t ORDER BY c1 LIMIT n OFFSET offset; Skip offset of rows and return the next n rows SELECT c1, c2 FROM t1, t2; Another way to perform cross join SQL CHEAT SHEET http://www.sqltutorial.org
  • 2. CREATE TABLE t( c1 INT, c2 INT, c3 VARCHAR, PRIMARY KEY (c1,c2) ); Set c1 and c2 as a primary key CREATE TABLE t ( id INT PRIMARY KEY, name VARCHAR NOT NULL, price INT DEFAULT 0 ); Create a new table with three columns INSERT INTO t(column_list) VALUES(value_list); Insert one row into a table INSERT INTO t(column_list) VALUES (value_list), (value_list), ….; Insert multiple rows into a table INSERT INTO t1(column_list) SELECT column_list FROM t2; Insert rows from t2 into t1 UPDATE t SET c1 = new_value, c2 = new_value WHERE condition; Update values in the column c1, c2 that match the condition DELETE FROM t; Delete all data in a table DELETE FROM t WHERE condition; Delete subset of rows in a table DROP TABLE t ; Delete the table from the database ALTER TABLE t ADD column; Add a new column to the table ALTER TABLE t DROP COLUMN c ; Drop column c from the table CREATE TABLE t1( c1 INT PRIMARY KEY, c2 INT, FOREIGN KEY (c2) REFERENCES t2(c2) ); Set c2 column as a foreign key CREATE TABLE t( c1 INT, c1 INT, UNIQUE(c2,c3) ); Make the values in c1 and c2 unique CREATE TABLE t( c1 INT, c2 INT, CHECK(c1> 0 AND c1 >= c2) ); Ensure c1 > 0 and values in c1 >= c2 CREATE TABLE t( c1 INT PRIMARY KEY, c2 VARCHAR NOT NULL ); Set values in c2 column not NULL TRUNCATE TABLE t; Remove all data in a table UPDATE t SET c1 = new_value; Update new value in the column c1 for all rows MANAGING TABLES USING SQL CONSTRAINTS MODIFYING DATA ALTER TABLE t ADD constraint; Add a constraint Rename a table from t1 to t2 ALTER TABLE t DROP constraint; Drop a constraint ALTER TABLE t1 RENAME c1 TO c2 ; Rename column c1 to c2 SQL CHEAT SHEET http://www.sqltutorial.org
  • 3. CREATE INDEX idx_name ON t(c1,c2); Create an index on c1 and c2 of the table t MANAGING INDEXES CREATE VIEW v(c1,c2) AS SELECT c1, c2 FROM t; Create a new view that consists of c1 and c2 MANAGING VIEWS MANAGING TRIGGERS SQL CHEAT SHEET http://www.sqltutorial.org DROP VIEW view_name Delete a view DROP INDEX idx_name; Drop an index CREATE VIEW v(c1,c2) AS SELECT c1, c2 FROM t; WITH [CASCADED | LOCAL] CHECK OPTION; Create a new view with check option CREATE RECURSIVE VIEW v AS select-statement -- anchor part UNION [ALL] select-statement; -- recursive part Create a recursive view CREATE OR MODIFY TRIGGER trigger_name WHEN EVENT ON table_name TRIGGER_TYPE EXECUTE stored_procedure; Create or modify a trigger DROP TRIGGER trigger_name Delete a specific trigger CREATE UNIQUE INDEX idx_name ON t(c3,c4); Create a unique index on c3, c4 of the table t SQL AGGREGATE FUNCTIONS AVG returns the average of a list CREATE TEMPORARY VIEW v AS SELECT c1, c2 FROM t; Create a temporary view WHEN • BEFORE – invoke before the event occurs • AFTER – invoke after the event occurs EVENT • INSERT – invoke for INSERT • UPDATE – invoke for UPDATE • DELETE – invoke for DELETE TRIGGER_TYPE • FOR EACH ROW • FOR EACH STATEMENT CREATE TRIGGER before_insert_person BEFORE INSERT ON person FOR EACH ROW EXECUTE stored_procedure; Create a trigger invoked before a new row is inserted into the person table COUNT returns the number of elements of a list SUM returns the total of a list MAX returns the maximum value in a list MIN returns the minimum value in a list