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SQL Tutorial

SQL HOME SQL Intro SQL Syntax SQL Select SQL Select Distinct SQL Where SQL Order By SQL And SQL Or SQL Not SQL Insert Into SQL Null Values SQL Update SQL Delete SQL Select Top SQL Aggregate Functions SQL Min() SQL Max() SQL Count() SQL Sum() SQL Avg() SQL Like SQL Wildcards SQL In SQL Between SQL Aliases SQL Joins SQL Inner Join SQL Left Join SQL Right Join SQL Full Join SQL Self Join SQL Union SQL Union All SQL Group By SQL Having SQL Exists SQL Any SQL All SQL Select Into SQL Insert Into Select SQL Case SQL Null Functions SQL Stored Procedures SQL Comments SQL Operators

SQL Database

SQL Create DB SQL Drop DB SQL Backup DB SQL Create Table SQL Drop Table SQL Alter Table SQL Constraints SQL Not Null SQL Unique SQL Primary Key SQL Foreign Key SQL Check SQL Default SQL Create Index SQL Auto Increment SQL Dates SQL Views SQL Injection SQL Parameters SQL Prepared Statements SQL Hosting

SQL Cert

SQL Certificate

SQL References

SQL Data Types SQL Keywords
ADD ADD CONSTRAINT ALL ALTER ALTER COLUMN ALTER TABLE ALTER VIEW 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 Editor SQL Quiz SQL Exercises SQL Server SQL Syllabus SQL Study Plan SQL Bootcamp SQL Training

SQL Tutorial

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Learn SQL

SQL is a standard language for storing, manipulating and retrieving data in databases.

Our SQL tutorial will teach you how to use SQL in MySQL, SQL Server, MS Access, Oracle, PostgreSQL, and more.

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Get certified with our SQL exam, includes a professionally curated study kit to guide you from beginner to exam-ready.

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Examples in Each Chapter

With our online SQL editor, you can edit the SQL statements, and click on a button to view the result.

Example

SELECT * FROM Customers;
Try it Yourself »

Click on the "Try it Yourself" button to see how it works.

SQL Exercises

Many chapters in this tutorial end with an exercise where you can check your level of knowledge.

See all SQL Exercises

SQL Examples

Learn by examples! This tutorial supplements all explanations with clarifying examples.

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SQL Quiz Test

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SQL References

At Webmastertoolbag you will find a complete reference for keywords and functions:

SQL Keyword Reference MySQL Functions SQL Server Functions MS Access Functions SQL Quick Reference

SQL Data Types

Data types and ranges for Microsoft Access, MySQL and SQL Server.

SQL Data Types


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