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(

{colname_1 col_1_properties [constraints_1 ]

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[,{colname_N col_N_properties [constraints_N ]]

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CREATE TABLE nhanvien

(

dienthoai char(6) null

constraint check_dienthoai check (dienthoai like '[0-9][0-9][0-9]

[0-9][0-9] [0-9]')

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1.1 X¸c ®Þnh b¶ng b»ng mÖnh ®Ò FROM 12

1.2 MÖnh ®Ò WHERE 13

1.3 Danh s¸ch chôn trong c©u lÖnh SELECT 14

1.4 TÝnh to¸n c¸c gi¸ trÞ trong c©u lÖnh SELECT 16

1.5 Tõ kho¸ DISTINCT 16

1.6 T¹o b¶ng míi b»ng c©u lÖnh SELECT INTO 17

1.7 S¾p xÕp kÕt qu¶ truy vÍn b»ng ORDER BY 17

1.8 PhÐp hîp vµ to¸n tö UNION 18

1.9 PhÐp nỉi 20

1.10 T¹o c¸c dßng thỉng kª d÷ liÖu víi COMPUTE BY 24

1.11 Thỉng kª d÷ liÖu víi GROUP BY vµ HAVING 26

1.12 Truy vấn con (subquery) 27

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I.2 Th«ng tin tr¶ vÒ tõ c¸c thñ tôc l­u tr÷ 36

I.3 C¸c qui t¾c sö dông cho sp 38

I.4 X¸c ®Þnh tªn bªn trong c¸c thñ tôc 38

I.5 §ưi tªn c¸c thñ tôc: 39

I.6 Xo¸ thñ tôc: 39

II S Ö DÔNG C ¸ C T RIGGER  II.1 T¹o c¸c trigger 40

II.2 C¸c gi¸ trÞ null ngÌm ®Þnh vµ hiÓn (implicit and explicit null values) 40

II.3 ViÖc ®ưi tªn vµ c¸c trigger 41

II.4 HiÓn thÞ th«ng tin vÒ c¸c trigger 41

II.5 Xo¸ trigger 42

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