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ADD ADD CONSTRAINT ALTER ALTER COLUMN ALTER TABLE ALL AND ANY AS ASC BACKUP DATABASE BETWEEN CASE CHECK COLUMN CONSTRAINT CREATE CREATE DATABASE CREATE INDEX CREATE OR REPLACE VIEW CREATE TABLE CREATE PROCEDURE CREATE UNIQUE INDEX CREATE VIEW DATABASE DEFAULT DELETE DESC DISTINCT DROP DROP COLUMN DROP CONSTRAINT DROP DATABASE DROP DEFAULT DROP INDEX DROP TABLE DROP VIEW EXEC EXISTS FOREIGN KEY FROM FULL OUTER JOIN GROUP BY HAVING IN INDEX INNER JOIN INSERT INTO INSERT INTO SELECT IS NULL IS NOT NULL JOIN LEFT JOIN LIKE LIMIT NOT NOT NULL OR ORDER BY OUTER JOIN PRIMARY KEY PROCEDURE RIGHT JOIN ROWNUM SELECT SELECT DISTINCT SELECT INTO SELECT TOP SET TABLE TOP TRUNCATE TABLE UNION UNION ALL UNIQUE UPDATE VALUES VIEW WHERE
MySQL Functions
String Functions ASCII CHAR_LENGTH CHARACTER_LENGTH CONCAT CONCAT_WS FIELD FIND_IN_SET FORMAT INSERT INSTR LCASE LEFT LENGTH LOCATE LOWER LPAD LTRIM MID POSITION REPEAT REPLACE REVERSE RIGHT RPAD RTRIM SPACE STRCMP SUBSTR SUBSTRING SUBSTRING_INDEX TRIM UCASE UPPER Numeric Functions ABS ACOS ASIN ATAN ATAN2 AVG CEIL CEILING COS COT COUNT DEGREES DIV EXP FLOOR GREATEST LEAST LN LOG LOG10 LOG2 MAX MIN MOD PI POW POWER RADIANS RAND ROUND SIGN SIN SQRT SUM TAN TRUNCATE Date Functions ADDDATE ADDTIME CURDATE CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP CURTIME DATE DATEDIFF DATE_ADD DATE_FORMAT DATE_SUB DAY DAYNAME DAYOFMONTH DAYOFWEEK DAYOFYEAR EXTRACT FROM_DAYS HOUR LAST_DAY LOCALTIME LOCALTIMESTAMP MAKEDATE MAKETIME MICROSECOND MINUTE MONTH MONTHNAME NOW PERIOD_ADD PERIOD_DIFF QUARTER SECOND SEC_TO_TIME STR_TO_DATE SUBDATE SUBTIME SYSDATE TIME TIME_FORMAT TIME_TO_SEC TIMEDIFF TIMESTAMP TO_DAYS WEEK WEEKDAY WEEKOFYEAR YEAR YEARWEEK Advanced Functions BIN BINARY CASE CAST COALESCE CONNECTION_ID CONV CONVERT CURRENT_USER DATABASE IF IFNULL ISNULL LAST_INSERT_ID NULLIF SESSION_USER SYSTEM_USER USER VERSION
SQL Server Functions
String Functions ASCII CHAR CHARINDEX CONCAT Concat with + CONCAT_WS DATALENGTH DIFFERENCE FORMAT LEFT LEN LOWER LTRIM NCHAR PATINDEX QUOTENAME REPLACE REPLICATE REVERSE RIGHT RTRIM SOUNDEX SPACE STR STUFF SUBSTRING TRANSLATE TRIM UNICODE UPPER Numeric Functions ABS ACOS ASIN ATAN ATN2 AVG CEILING COUNT COS COT DEGREES EXP FLOOR LOG LOG10 MAX MIN PI POWER RADIANS RAND ROUND SIGN SIN SQRT SQUARE SUM TAN Date Functions CURRENT_TIMESTAMP DATEADD DATEDIFF DATEFROMPARTS DATENAME DATEPART DAY GETDATE GETUTCDATE ISDATE MONTH SYSDATETIME YEAR Advanced Functions CAST COALESCE CONVERT CURRENT_USER IIF ISNULL ISNUMERIC NULLIF SESSION_USER SESSIONPROPERTY SYSTEM_USER USER_NAME
MS Access Functions
String Functions Asc Chr Concat with & CurDir Format InStr InstrRev LCase Left Len LTrim Mid Replace Right RTrim Space Split Str StrComp StrConv StrReverse Trim UCase Numeric Functions Abs Atn Avg Cos Count Exp Fix Format Int Max Min Randomize Rnd Round Sgn Sqr Sum Val Date Functions Date DateAdd DateDiff DatePart DateSerial DateValue Day Format Hour Minute Month MonthName Now Second Time TimeSerial TimeValue Weekday WeekdayName Year Other Functions CurrentUser Environ IsDate IsNull IsNumeric
SQL Quick Ref

SQL Examples

SQL Examples

SQL CREATE Keyword

❮ SQL Keywords Reference

CREATE DATABASE

The CREATE DATABASE command is used is to create a new SQL database.

The following SQL creates a database called "testDB":

Example

CREATE DATABASE testDB;

Tip: Make sure you have admin privilege before creating any database. Once a database is created, you can check it in the list of databases with the following SQL command: SHOW DATABASES;

CREATE TABLE

The CREATE TABLE command creates a new table in the database.

The following SQL creates a table called "Persons" that contains five columns: PersonID, LastName, FirstName, Address, and City:

Example

CREATE TABLE Persons (
    PersonID int,
    LastName varchar(255),
    FirstName varchar(255),
    Address varchar(255),
    City varchar(255)
);
Try it Yourself »

CREATE TABLE Using Another Table

The following SQL creates a new table called "TestTables" (which is a copy of two columns of the "Customers" table): 

Example

CREATE TABLE TestTable AS
SELECT customername, contactname
FROM customers;
Try it Yourself »

CREATE INDEX

The CREATE INDEX command is used to create indexes in tables (allows duplicate values).

Indexes are used to retrieve data from the database very fast. The users cannot see the indexes, they are just used to speed up searches/queries.

The following SQL creates an index named "idx_lastname" on the "LastName" column in the "Persons" table:

CREATE INDEX idx_lastname
ON Persons (LastName);

If you want to create an index on a combination of columns, you can list the column names within the parentheses, separated by commas:

CREATE INDEX idx_pname
ON Persons (LastName, FirstName);

Note: The syntax for creating indexes varies among different databases. Therefore: Check the syntax for creating indexes in your database.

Note: Updating a table with indexes takes more time than updating a table without (because the indexes also need an update). So, only create indexes on columns that will be frequently searched against.

CREATE UNIQUE INDEX

The CREATE UNIQUE INDEX command creates a unique index on a table (no duplicate values allowed)

The following SQL creates an index named "uidx_pid" on the "PersonID" column in the "Persons" table:

CREATE UNIQUE INDEX uidx_pid
ON Persons (PersonID);

CREATE VIEW

The CREATE VIEW command creates a view.

A view is a virtual table based on the result set of an SQL statement.

The following SQL creates a view that selects all customers from Brazil:

Example

CREATE VIEW [Brazil Customers] AS
SELECT CustomerName, ContactName
FROM Customers
WHERE Country = "Brazil";
Try it Yourself »

CREATE OR REPLACE VIEW

The CREATE OR REPLACE VIEW command updates a view.

The following SQL adds the "City" column to the "Brazil Customers" view:

Example

CREATE OR REPLACE VIEW [Brazil Customers] AS
SELECT CustomerName, ContactName, City
FROM Customers
WHERE Country = "Brazil";
Try it Yourself »

Query The View

We can query the view above as follows:

Example

SELECT * FROM [Brazil Customers];
Try it Yourself »

CREATE PROCEDURE

The CREATE PROCEDURE command is used to create a stored procedure.

A stored procedure is a prepared SQL code that you can save, so the code can be reused over and over again.

The following SQL creates a stored procedure named "SelectAllCustomers" that selects all records from the "Customers" table:

Example

CREATE PROCEDURE SelectAllCustomers
AS
SELECT * FROM Customers
GO;

Execute the stored procedure above as follows:

Example

EXEC SelectAllCustomers;

❮ SQL Keywords Reference