Tham khảo từ khóa SQL
Tham chiếu từ khóa SQL này chứa các từ dành riêng trong SQL.
Từ khóa SQL
| Keyword | Description |
|---|---|
| ADD | Adds a column in an existing table |
| ADD CONSTRAINT | Adds a constraint after a table is already created |
| ALL | Returns true if all of the subquery values meet the condition |
| ALTER | Adds, deletes, or modifies columns in a table, or changes the data type of a column in a table |
| ALTER COLUMN | Changes the data type of a column in a table |
| ALTER TABLE | Adds, deletes, or modifies columns in a table |
| AND | Only includes rows where both conditions is true |
| ANY | Returns true if any of the subquery values meet the condition |
| AS | Renames a column or table with an alias |
| ASC | Sorts the result set in ascending order |
| BACKUP DATABASE | Creates a back up of an existing database |
| BETWEEN | Selects values within a given range |
| CASE | Creates different outputs based on conditions |
| CHECK | A constraint that limits the value that can be placed in a column |
| COLUMN | Changes the data type of a column or deletes a column in a table |
| CONSTRAINT | Adds or deletes a constraint |
| CREATE | Creates a database, index, view, table, or procedure |
| CREATE DATABASE | Creates a new SQL database |
| CREATE INDEX | Creates an index on a table (allows duplicate values) |
| CREATE OR REPLACE VIEW | Updates a view |
| CREATE TABLE | Creates a new table in the database |
| CREATE PROCEDURE | Creates a stored procedure |
| CREATE UNIQUE INDEX | Creates a unique index on a table (no duplicate values) |
| CREATE VIEW | Creates a view based on the result set of a SELECT statement |
| DATABASE | Creates or deletes an SQL database |
| DEFAULT | A constraint that provides a default value for a column |
| DELETE | Deletes rows from a table |
| DESC | Sorts the result set in descending order |
| DISTINCT | Selects only distinct (different) values |
| DROP | Deletes a column, constraint, database, index, table, or view |
| DROP COLUMN | Deletes a column in a table |
| DROP CONSTRAINT | Deletes a UNIQUE, PRIMARY KEY, FOREIGN KEY, or CHECK constraint |
| DROP DATABASE | Deletes an existing SQL database |
| DROP DEFAULT | Deletes a DEFAULT constraint |
| DROP INDEX | Deletes an index in a table |
| DROP TABLE | Deletes an existing table in the database |
| DROP VIEW | Deletes a view |
| EXEC | Executes a stored procedure |
| EXISTS | Tests for the existence of any record in a subquery |
| FOREIGN KEY | A constraint that is a key used to link two tables together |
| FROM | Specifies which table to select or delete data from |
| FULL OUTER JOIN | Returns all rows when there is a match in either left table or right table |
| GROUP BY | Groups the result set (used with aggregate functions: COUNT, MAX, MIN, SUM, AVG) |
| HAVING | Used instead of WHERE with aggregate functions |
| IN | Allows you to specify multiple values in a WHERE clause |
| INDEX | Creates or deletes an index in a table |
| INNER JOIN | Returns rows that have matching values in both tables |
| INSERT INTO | Inserts new rows in a table |
| INSERT INTO SELECT | Copies data from one table into another table |
| IS NULL | Tests for empty values |
| IS NOT NULL | Tests for non-empty values |
| JOIN | Joins tables |
| LEFT JOIN | Returns all rows from the left table, and the matching rows from the right table |
| LIKE | Searches for a specified pattern in a column |
| LIMIT | Specifies the number of records to return in the result set |
| NOT | Only includes rows where a condition is not true |
| NOT NULL | A constraint that enforces a column to not accept NULL values |
| OR | Includes rows where either condition is true |
| ORDER BY | Sorts the result set in ascending or descending order |
| OUTER JOIN | Returns all rows when there is a match in either left table or right table |
| PRIMARY KEY | A constraint that uniquely identifies each record in a database table |
| PROCEDURE | A stored procedure |
| RIGHT JOIN | Returns all rows from the right table, and the matching rows from the left table |
| ROWNUM | Specifies the number of records to return in the result set |
| SELECT | Selects data from a database |
| SELECT DISTINCT | Selects only distinct (different) values |
| SELECT INTO | Copies data from one table into a new table |
| SELECT TOP | Specifies the number of records to return in the result set |
| SET | Specifies which columns and values that should be updated in a table |
| TABLE | Creates a table, or adds, deletes, or modifies columns in a table, or deletes a table or data inside a table |
| TOP | Specifies the number of records to return in the result set |
| TRUNCATE TABLE | Deletes the data inside a table, but not the table itself |
| UNION | Combines the result set of two or more SELECT statements (only distinct values) |
| UNION ALL | Combines the result set of two or more SELECT statements (allows duplicate values) |
| UNIQUE | A constraint that ensures that all values in a column are unique |
| UPDATE | Updates existing rows in a table |
| VALUES | Specifies the values of an INSERT INTO statement |
| VIEW | Creates, updates, or deletes a view |
| WHERE | Filters a result set to include only records that fulfill a specified condition |
