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57. - ?
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58. ?
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59. - ?
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60. - ?
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1. .
2. .
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62. - ?
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63. - ?
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3.24. - . 3.1 (. 3.1) , →(, ). , - , →(, ).
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66. SELECT- SQL?
:
;
;
.
67. SELECT- SQL?
SELECT
FROM -
WHERE ;
SELECT . . , , .
-, - *.
SELECT name, surname
FROM student;
68. SELECT- SQL?
- DISTINCT
SELECT- DISTINCT ().
SELECT DISTINCT city
FROM student;
AND, OR, NOT
WHERE
= > >= < <= < >
AND, OR, NOT.
:
SELECT surname, name, city
FROM student
WHERE city= "" AND birthday > '1990-12-25';
IN
IN ( ) NOT IN ( ) .
,
SELECT *
FROM exam_marks
WHERE city IN ("", "");
,
SELECT *
FROM exam_marks
WHERE mark NOT IN (3, 5);
BETWEEN
BETWEEN
SELECT *
FROM subject
WHERE city BETWEEN "" AND "";
LIKE
, : _ , , % - , . ,
SELECT *
FROM student
WHERE surname LIKE %;
, ,
SELECT *
FROM subject
WHERE subj_name LIKE _%;
ORDER BY
ORDER BY . (ASC) (DESC). ,
SELECT *
FROM student
ORDER BY city;
:
SELECT *
FROM student
ORDER BY city DESC;
69. SQL-?
SQL- ϳ :
- ϳ (), ( ).
- ' , , .
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- ϳ SQL-', , . SQL- , , SQL-'.
