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+# Quick SQL Cheatsheet
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#quick-sql-cheatsheet)
+
+A quick reminder of all relevant SQL queries and examples on how to use them.
+
+This repository is constantly being updated and added to by the community. Pull requests are welcome. Enjoy!
+
+# Table of Contents
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#table-of-contents)
+
+1. [Finding Data Queries.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#find)
+2. [Data Modification Queries.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#modify)
+3. [Reporting Queries.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#report)
+4. [Join Queries.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#joins)
+5. [View Queries.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#view)
+6. [Altering Table Queries.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#alter)
+7. [Creating Table Query.](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#create)
+
+# 1. Finding Data Queries
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#1-finding-data-queries)
+
+### **SELECT**: used to select data from a database
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#select-used-to-select-data-from-a-database)
+
+- `SELECT` * `FROM` table_name;
+
+### **DISTINCT**: filters away duplicate values and returns rows of specified column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#distinct-filters-away-duplicate-values-and-returns-rows-of-specified-column)
+
+- `SELECT DISTINCT` column_name;
+
+### **WHERE**: used to filter records/rows
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#where-used-to-filter-recordsrows)
+
+- `SELECT` column1, column2 `FROM` table_name `WHERE` condition;
+- `SELECT` * `FROM` table_name `WHERE` condition1 `AND` condition2;
+- `SELECT` * `FROM` table_name `WHERE` condition1 `OR` condition2;
+- `SELECT` * `FROM` table_name `WHERE NOT` condition;
+- `SELECT` * `FROM` table_name `WHERE` condition1 `AND` (condition2 `OR` condition3);
+- `SELECT` * `FROM` table_name `WHERE EXISTS` (`SELECT` column_name `FROM` table_name `WHERE` condition);
+
+### **ORDER BY**: used to sort the result-set in ascending or descending order
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#order-by-used-to-sort-the-result-set-in-ascending-or-descending-order)
+
+- `SELECT` * `FROM` table_name `ORDER BY` column;
+- `SELECT` * `FROM` table_name `ORDER BY` column `DESC`;
+- `SELECT` * `FROM` table_name `ORDER BY` column1 `ASC`, column2 `DESC`;
+
+### **SELECT TOP**: used to specify the number of records to return from top of table
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#select-top-used-to-specify-the-number-of-records-to-return-from-top-of-table)
+
+- `SELECT TOP` number columns_names `FROM` table_name `WHERE` condition;
+- `SELECT TOP` percent columns_names `FROM` table_name `WHERE` condition;
+- Not all database systems support `SELECT TOP`. The MySQL equivalent is the `LIMIT` clause
+- `SELECT` column_names `FROM` table_name `LIMIT` offset, count;
+
+### **LIKE**: operator used in a WHERE clause to search for a specific pattern in a column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#like-operator-used-in-a-where-clause-to-search-for-a-specific-pattern-in-a-column)
+
+- % (percent sign) is a wildcard character that represents zero, one, or multiple characters
+- _ (underscore) is a wildcard character that represents a single character
+- `SELECT` column_names `FROM` table_name `WHERE` column_name `LIKE` pattern;
+- `LIKE` ‘a%’ (find any values that start with “a”)
+- `LIKE` ‘%a’ (find any values that end with “a”)
+- `LIKE` ‘%or%’ (find any values that have “or” in any position)
+- `LIKE` ‘_r%’ (find any values that have “r” in the second position)
+- `LIKE` ‘a_%_%’ (find any values that start with “a” and are at least 3 characters in length)
+- `LIKE` ‘[a-c]%’ (find any values starting with “a”, “b”, or “c”
+
+### **IN**: operator that allows you to specify multiple values in a WHERE clause
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#in-operator-that-allows-you-to-specify-multiple-values-in-a-where-clause)
+
+- essentially the IN operator is shorthand for multiple OR conditions
+- `SELECT` column_names `FROM` table_name `WHERE` column_name `IN` (value1, value2, …);
+- `SELECT` column_names `FROM` table_name `WHERE` column_name `IN` (`SELECT STATEMENT`);
+
+### **BETWEEN**: operator selects values within a given range inclusive
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#between-operator-selects-values-within-a-given-range-inclusive)
+
+- `SELECT` column_names `FROM` table_name `WHERE` column_name `BETWEEN` value1 `AND` value2;
+- `SELECT` * `FROM` Products `WHERE` (column_name `BETWEEN` value1 `AND` value2) `AND NOT` column_name2 `IN` (value3, value4);
+- `SELECT` * `FROM` Products `WHERE` column_name `BETWEEN` #01/07/1999# AND #03/12/1999#;
+
+### **NULL**: values in a field with no value
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#null-values-in-a-field-with-no-value)
+
+- `SELECT` * `FROM` table_name `WHERE` column_name `IS NULL`;
+- `SELECT` * `FROM` table_name `WHERE` column_name `IS NOT NULL`;
+
+### **AS**: aliases are used to assign a temporary name to a table or column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#as-aliases-are-used-to-assign-a-temporary-name-to-a-table-or-column)
+
+- `SELECT` column_name `AS` alias_name `FROM` table_name;
+- `SELECT` column_name `FROM` table_name `AS` alias_name;
+- `SELECT` column_name `AS` alias_name1, column_name2 `AS` alias_name2;
+- `SELECT` column_name1, column_name2 + ‘, ‘ + column_name3 `AS` alias_name;
+
+### **UNION**: set operator used to combine the result-set of two or more SELECT statements
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#union-set-operator-used-to-combine-the-result-set-of-two-or-more-select-statements)
+
+- Each SELECT statement within UNION must have the same number of columns
+- The columns must have similar data types
+- The columns in each SELECT statement must also be in the same order
+- `SELECT` columns_names `FROM` table1 `UNION SELECT` column_name `FROM` table2;
+- `UNION` operator only selects distinct values, `UNION ALL` will allow duplicates
+
+### **INTERSECT**: set operator which is used to return the records that two SELECT statements have in common
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#intersect-set-operator-which-is-used-to-return-the-records-that-two-select-statements-have-in-common)
+
+- Generally used the same way as **UNION** above
+- `SELECT` columns_names `FROM` table1 `INTERSECT SELECT` column_name `FROM` table2;
+
+### **EXCEPT**: set operator used to return all the records in the first SELECT statement that are not found in the second SELECT statement
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#except-set-operator-used-to-return-all-the-records-in-the-first-select-statement-that-are-not-found-in-the-second-select-statement)
+
+- Generally used the same way as **UNION** above
+- `SELECT` columns_names `FROM` table1 `EXCEPT SELECT` column_name `FROM` table2;
+
+### **ANY|ALL**: operator used to check subquery conditions used within a WHERE or HAVING clauses
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#anyall-operator-used-to-check-subquery-conditions-used-within-a-where-or-having-clauses)
+
+- The `ANY` operator returns true if any subquery values meet the condition
+- The `ALL` operator returns true if all subquery values meet the condition
+- `SELECT` columns_names `FROM` table1 `WHERE` column_name operator (`ANY`|`ALL`) (`SELECT` column_name `FROM` table_name `WHERE` condition);
+
+### **GROUP BY**: statement often used with aggregate functions (COUNT, MAX, MIN, SUM, AVG) to group the result-set by one or more columns
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#group-by-statement-often-used-with-aggregate-functions-count-max-min-sum-avg-to-group-the-result-set-by-one-or-more-columns)
+
+- `SELECT` column_name1, COUNT(column_name2) `FROM` table_name `WHERE` condition `GROUP BY` column_name1 `ORDER BY` COUNT(column_name2) DESC;
+
+### **HAVING**: this clause was added to SQL because the WHERE keyword could not be used with aggregate functions
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#having-this-clause-was-added-to-sql-because-the-where-keyword-could-not-be-used-with-aggregate-functions)
+
+- `SELECT` `COUNT`(column_name1), column_name2 `FROM` table `GROUP BY` column_name2 `HAVING` `COUNT(`column_name1`)` > 5;
+
+### **WITH**: often used for retrieving hierarchical data or re-using temp result set several times in a query. Also referred to as "Common Table Expression"
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#with-often-used-for-retrieving-hierarchical-data-or-re-using-temp-result-set-several-times-in-a-query-also-referred-to-as-common-table-expression)
+
+- `WITH RECURSIVE` cte `AS` (  
+      `SELECT` c0.* `FROM` categories `AS` c0 `WHERE` id = 1 `# Starting point`  
+      `UNION ALL`  
+      `SELECT` c1.* `FROM` categories `AS` c1 `JOIN` cte `ON` c1.parent_category_id = cte.id  
+    )  
+    `SELECT` *  
+    `FROM` cte
+
+# 2. Data Modification Queries
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#2-data-modification-queries)
+
+### **INSERT INTO**: used to insert new records/rows in a table
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#insert-into-used-to-insert-new-recordsrows-in-a-table)
+
+- `INSERT INTO` table_name (column1, column2) `VALUES` (value1, value2);
+- `INSERT INTO` table_name `VALUES` (value1, value2 …);
+
+### **UPDATE**: used to modify the existing records in a table
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#update-used-to-modify-the-existing-records-in-a-table)
+
+- `UPDATE` table_name `SET` column1 = value1, column2 = value2 `WHERE` condition;
+- `UPDATE` table_name `SET` column_name = value;
+
+### **DELETE**: used to delete existing records/rows in a table
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#delete-used-to-delete-existing-recordsrows-in-a-table)
+
+- `DELETE FROM` table_name `WHERE` condition;
+- `DELETE` * `FROM` table_name;
+
+# 3. Reporting Queries
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#3-reporting-queries)
+
+### **COUNT**: returns the # of occurrences
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#count-returns-the--of-occurrences)
+
+- `SELECT COUNT (DISTINCT` column_name`)`;
+
+### **MIN() and MAX()**: returns the smallest/largest value of the selected column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#min-and-max-returns-the-smallestlargest-value-of-the-selected-column)
+
+- `SELECT MIN (`column_names`) FROM` table_name `WHERE` condition;
+- `SELECT MAX (`column_names`) FROM` table_name `WHERE` condition;
+
+### **AVG()**: returns the average value of a numeric column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#avg-returns-the-average-value-of-a-numeric-column)
+
+- `SELECT AVG (`column_name`) FROM` table_name `WHERE` condition;
+
+### **SUM()**: returns the total sum of a numeric column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#sum-returns-the-total-sum-of-a-numeric-column)
+
+- `SELECT SUM (`column_name`) FROM` table_name `WHERE` condition;
+
+# 4. Join Queries
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#4-join-queries)
+
+### **INNER JOIN**: returns records that have matching value in both tables
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#inner-join-returns-records-that-have-matching-value-in-both-tables)
+
+- `SELECT` column_names `FROM` table1 `INNER JOIN` table2 `ON` table1.column_name=table2.column_name;
+- `SELECT` table1.column_name1, table2.column_name2, table3.column_name3 `FROM` ((table1 `INNER JOIN` table2 `ON` relationship) `INNER JOIN` table3 `ON` relationship);
+
+### **LEFT (OUTER) JOIN**: returns all records from the left table (table1), and the matched records from the right table (table2)
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#left-outer-join-returns-all-records-from-the-left-table-table1-and-the-matched-records-from-the-right-table-table2)
+
+- `SELECT` column_names `FROM` table1 `LEFT JOIN` table2 `ON` table1.column_name=table2.column_name;
+
+### **RIGHT (OUTER) JOIN**: returns all records from the right table (table2), and the matched records from the left table (table1)
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#right-outer-join-returns-all-records-from-the-right-table-table2-and-the-matched-records-from-the-left-table-table1)
+
+- `SELECT` column_names `FROM` table1 `RIGHT JOIN` table2 `ON` table1.column_name=table2.column_name;
+
+### **FULL (OUTER) JOIN**: returns all records when there is a match in either left or right table
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#full-outer-join-returns-all-records-when-there-is-a-match-in-either-left-or-right-table)
+
+- `SELECT` column_names `FROM` table1 `FULL OUTER JOIN` table2 `ON` table1.column_name=table2.column_name;
+
+### **Self JOIN**: a regular join, but the table is joined with itself
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#self-join-a-regular-join-but-the-table-is-joined-with-itself)
+
+- `SELECT` column_names `FROM` table1 T1, table1 T2 `WHERE` condition;
+
+# 5. View Queries
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#5-view-queries)
+
+### **CREATE**: create a view
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#create-create-a-view)
+
+- `CREATE VIEW` view_name `AS SELECT` column1, column2 `FROM` table_name `WHERE` condition;
+
+### **SELECT**: retrieve a view
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#select-retrieve-a-view)
+
+- `SELECT` * `FROM` view_name;
+
+### **DROP**: drop a view
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#drop-drop-a-view)
+
+- `DROP VIEW` view_name;
+
+# 6. Altering Table Queries
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#6-altering-table-queries)
+
+### **ADD**: add a column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#add-add-a-column)
+
+- `ALTER TABLE` table_name `ADD` column_name column_definition;
+
+### **MODIFY**: change data type of column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#modify-change-data-type-of-column)
+
+- `ALTER TABLE` table_name `MODIFY` column_name column_type;
+
+### **DROP**: delete a column
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#drop-delete-a-column)
+
+- `ALTER TABLE` table_name `DROP COLUMN` column_name;
+
+# 7. Creating Table Query
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#7-creating-table-query)
+
+### **CREATE**: create a table
+
+[](https://github.com/enochtangg/quick-SQL-cheatsheet?tab=readme-ov-file#create-create-a-table)
+
+- `CREATE TABLE` table_name `(`  
+    `column1` `datatype`,  
+    `column2` `datatype`,  
+    `column3` `datatype`,  
+    `column4` `datatype`,  
+    `);`
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