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SQL SELECT
Store_Information ±í¸ñ
store_name
Sales
Date
Los Angeles
$1500
Jan-05-1999
San Diego
$250
Jan-07-1999
Los Angeles
$300
Jan-08-1999
Boston
$700
Jan-08-1999
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SELECT store_name from Store_Information
½á¹û:
store_name
Los Angeles
San Diego
Los Angeles
Boston
SQL DISTINCT
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Store_Information±í¸ñ
store_name
Sales
Date
Los Angeles
$1500
Jan-05-1999
San Diego
$250
Jan-07-1999
Los Angeles
$300
Jan-08-1999
Boston
$700
Jan-08-1999
ÎÒÃǾʹòÈ룬
SELECT DISTINCT store_name from Store_Information
½á¹û:
store_name
Los Angeles
San Diego
Boston
SQL WHERE
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Store_Information
store_name
Sales
Date
Los Angeles
$1500
Jan-05-1999
San Diego
$250
Jan-07-1999
Los Angeles
$300
Jan-08-1999
Boston
$700
Jan-08-1999
±í¸ñ
ÎÒÃǾʹòÈ룬
SELECT store_name
from Store_Information
WHERE Sales > 1000
½á¹û:
store_name
Los Angeles
SQL AND OR
ÎÒÃÇÈôÒªÔÚ Store_Information±í¸ñÖÐÑ¡³öËùÓÐ Sales ¸ßÓÚ $1,000 »òÊÇ Sales ÔÚ $500 ¼° $275 Ö®¼äµÄ×ÊÁϵĻ°£¬
Store_Information ±í¸ñ
store_name
Sales
Date
Los Angeles
$1500
Jan-05-1999
San Diego
$250
Jan-07-1999
San Francisco
$300
Jan-08-1999
Boston
$700
Jan-08-1999
ÎÒÃǾʹòÈ룬
SELECT store_name
from Store_Information
WHERE Sales > 1000
OR (Sales < 500 AND Sales > 275)
½á¹û:
store_name
Los Angeles
San Francisco
SQL IN
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Store_Information ±í¸ñ
store_name
Sales
Date
Los
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