This document contains information about SQL queries, including: 1. The structure and components of a basic SELECT query with clauses like SELECT, FROM, WHERE, GROUP BY, HAVING, ORDER BY, LIMIT. 2. Types of tables that can be used in queries like permanent, temporary, and virtual tables. 3. Operators that can be used in WHERE clauses like =, <, >, BETWEEN, IN, LIKE, AND, OR, NOT. 4. Examples of JOINs, aggregate functions, INSERT, UPDATE, DELETE statements.

2. 1. Есть ли у вас разрешение на выполнение
выражения?
2. Есть ли у вас разрешения на доступ к необходимым
данным?
3. Правилен ли синтаксис выражения?
4. Оптимизация
5. План выполнения
6. Результирующий набор

3. SELECT
[ALL | DISTINCT | DISTINCTROW ]
[HIGH_PRIORITY]
[STRAIGHT_JOIN]
[SQL_SMALL_RESULT] [SQL_BIG_RESULT]
[SQL_BUFFER_RESULT]
[SQL_CACHE | SQL_NO_CACHE]
[SQL_CALC_FOUND_ROWS]
select_expr [, select_expr ...]
[FROM table_references
[WHERE where_condition]
[GROUP BY {col_name | expr | position}
[ASC | DESC], ... [WITH ROLLUP]]
[HAVING where_condition]
[ORDER BY {col_name | expr | position}
[ASC | DESC], ...]
[LIMIT {[offset,] row_count | row_count OFFSET offset}]

4. 1. Постоянные таблицы
2. Временные таблицы
3. Виртуальные таблицы (представления)

5. 1. =
2. !=, <>
3. >, <, >=, <=
4. BETWEEN
5. IN
6. LIKE (_, %)
1. OR
2. AND
3. NOT

6. SELECT DISTINCT v.fname, v.lname, i.year, i.location, i.report_file
FROM Incident AS i
LEFT JOIN V(ictim?)... -- presumably v.incident_id = i.id
LEFT JOIN Keyword AS k ON k.incident_id = i.id
WHERE i.year BETWEEN 1947 AND 1966
AND i.type = 'HOMICIDE'
AND v.sex = 'F'
AND i.status = 'UNSOLVED'
AND ...
OR v.fname IN ('Mari', 'Magda')
OR SUBSTR ...
AND (k.keyword IN ('rape', 'decapitation', 'dismemberment', 'fire', 'altar', 'priest', 'prostitute')
...
AND SUBSTR(v.fname, 1, 1) = 'R' AND SUBSTR(v.lname, 1, 1) = 'L');

7. fname lname year location report_file
Anna Wedin 1956Mark FULL POLICE REPORT NOT DIGITIZED
Linda Janson 1955Mariestad FULL POLICE REPORT NOT DIGITIZED
Simone Grau 1958Goteborg FULL POLICE REPORT NOT DIGITIZED
Lea Persson 1962Uddevalla FULL POLICE REPORT NOT DIGITIZED
Kajsa Severin 1962Dals-Ed FULL POLICE REPORT NOT DIGITIZED

8. CASE case_value
WHEN when_value THEN statement_list
[WHEN when_value THEN statement_list] ...
[ELSE statement_list]
END CASE
Or:
CASE
WHEN search_condition THEN statement_list
[WHEN search_condition THEN statement_list] ...
[ELSE statement_list]
END CASE
IF (EXP1, EXP2, EXP3)

9. 1. Группировка по одному столбцу
2. Группировка по нескольким столбцам
3. Группировка по средствам выражений
4. WITH ROLLUP

10. Name Description
AVG() Return the average value of the argument
BIT_AND() Return bitwise and
BIT_OR() Return bitwise or
BIT_XOR() Return bitwise xor
COUNT(DISTINCT) Return the count of a number of different values
COUNT() Return a count of the number of rows returned
GROUP_CONCAT() Return a concatenated string
MAX() Return the maximum value
MIN() Return the minimum value
STD() Return the population standard deviation
STDDEV() Return the population standard deviation
SUM() Return the sum
VARIANCE() Return the population standard variance

11. SELECT column_name, aggregate_function(column_name)
FROM table_name
WHERE column_name operator value
GROUP BY column_name
HAVING aggregate_function(column_name) operator value

12. ORDER BY {col_name | expr | position}
[ASC | DESC], ...
LIMIT {[offset,] row_count | row_count OFFSET offset}

13. INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name [(col_name,...)]
{VALUES | VALUE} ({expr | DEFAULT},...),(...),...
[ ON DUPLICATE KEY UPDATE
col_name=expr
[, col_name=expr] ... ]
Or:
INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name
SET col_name={expr | DEFAULT}, ...
[ ON DUPLICATE KEY UPDATE
col_name=expr
[, col_name=expr] ... ]
Or:
INSERT [LOW_PRIORITY | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name [(col_name,...)]
SELECT ...
[ ON DUPLICATE KEY UPDATE
col_name=expr
[, col_name=expr] ... ]

14. INSERT INTO tbl_temp2 (fld_id)
SELECT
tbl_temp1.fld_order_id
FROM
tbl_temp1
WHERE
tbl_temp1.fld_order_id > 100;
INSERT INTO table (a,b,c) VALUES (1,2,3)
ON DUPLICATE KEY UPDATE c=c+1;
INSERT INTO table (a,b,c) VALUES (1,2,3),(4,5,6)
ON DUPLICATE KEY UPDATE c=VALUES(a)+VALUES(b);

15. UPDATE [LOW_PRIORITY] [IGNORE] table_reference
SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
[WHERE where_condition]
[ORDER BY ...]
[LIMIT row_count]
Multiple-table syntax:
UPDATE [LOW_PRIORITY] [IGNORE] table_references
SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
[WHERE where_condition]

16. DELETE [LOW_PRIORITY] [QUICK] [IGNORE] FROM tbl_name
[WHERE where_condition]
[ORDER BY ...]
[LIMIT row_count]
Multiple-table syntax:
DELETE [LOW_PRIORITY] [QUICK] [IGNORE]
tbl_name[.*] [, tbl_name[.*]] ...
FROM table_references
[WHERE where_condition]
Or:
DELETE [LOW_PRIORITY] [QUICK] [IGNORE]
FROM tbl_name[.*] [, tbl_name[.*]] ...
USING table_references
[WHERE where_condition]

17. DELETE
t1, t2
FROM
t1
INNER JOIN t2
INNER JOIN t3
WHERE
t1.id=t2.id AND t2.id=t3.id;
Or:
DELETE FROM
t1, t2
USING
t1
INNER JOIN t2
INNER JOIN t3
WHERE
t1.id=t2.id AND t2.id=t3.id;