SQL 语法
Select all the records from a specific table ("Customers")

实例解析

SQL SELECT
SELECT Column SELECT *

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SQL SELECT DISTINCT
SELECT DISTINCT SELECT COUNT(DISTINCT column_name) SELECT COUNT(DISTINCT column_name) workaround for MS Access

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SQL WHERE
WHERE Clause Text Fields vs. Numeric Fields

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SQL AND, OR and NOT Operators
AND OR NOT Combining AND, OR and NOT

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SQL ORDER BY
ORDER BY ORDER BY DESC ORDER BY Several Columns

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SQL INSERT INTO
INSERT INTO Insert data in specific columns

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SQL NULL Values
IS NULL Operator IS NOT NULL Operator

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SQL Update
UPDATE Table UPDATE Multiple Records UPDATE Warning (if you omit the WHERE clause, all records will be updated)

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SQL DELETE
DELETE DELETE All Records

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SQL SELECT TOP
SELECT TOP LIMIT SELECT TOP PERCENT SELECT TOP and add a WHERE Clause

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SQL MIN() and MAX()
MIN() MAX()

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SQL COUNT, AVG() and SUM()
COUNT() AVG() SUM()

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SQL LIKE
LIKE - select all table rows starting with "a" LIKE - select all table rows ending with "a" LIKE - select all table rows that have "or" in any position LIKE - select all table rows that have "r" in the second position LIKE - select all table rows that starts with "a" and ends with "o" LIKE - select all table rows that does NOT start with "a"

实例解析

SQL Wildcards
Using the % Wildcard Using the _ Wildcard Using the [charlist] Wildcard Using the [!charlist] Wildcard

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SQL IN
IN NOT IN

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SQL BETWEEN
BETWEEN NOT BETWEEN BETWEEN with IN BETWEEN Text Values NOT BETWEEN Text Values

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SQL Aliases
Alias for Columns Two Aliases Alias for Tables

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SQL Joins
INNER JOIN LEFT JOIN RIGHT JOIN Self JOIN

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SQL UNION
UNION UNION ALL UNION With WHERE UNION ALL With WHERE

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SQL GROUP BY
GROUP BY GROUP BY and ORDER BY GROUP BY With JOIN

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SQL HAVING
HAVING and GROUP BY HAVING and ORDER BY

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SQL EXISTS
EXISTS

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SQL ANY and ALL
ANY ALL

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SQL INSERT INTO SELECT
INSERT INTO SELECT INSERT INTO SELECT with WHERE

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SQL CASE
CASE 1 CASE 2

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SQL Comments
Single Line Comments Single Line Comments At The End Of a Line Multi-line Comments

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SQL Database

SQL Database tutorials can be found here:

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 Index SQL Auto Increment SQL Dates SQL Views SQL Injection SQL Hosting