oracle查询,Oracle数据库查询技巧与优化战略

当然，Oracle是一个联系型数据库办理体系，它运用SQL（结构化查询言语）来查询和办理数据。下面是一些根本的Oracle查询示例：

1. 查询一切数据： ```sql SELECT FROM table_name; ```

2. 查询特定列： ```sql SELECT column1, column2 FROM table_name; ```

3. 条件查询： ```sql SELECT FROM table_name WHERE condition; ```

4. 排序查询： ```sql SELECT FROM table_name ORDER BY column_name; ```

5. 分组查询： ```sql SELECT column_name, COUNT FROM table_name GROUP BY column_name; ```

6. 衔接查询： ```sql SELECT FROM table1 JOIN table2 ON table1.column_name = table2.column_name; ```

7. 子查询： ```sql SELECT FROM table_name WHERE column_name IN ; ```

8. 更新数据： ```sql UPDATE table_name SET column_name = value WHERE condition; ```

9. 删去数据： ```sql DELETE FROM table_name WHERE condition; ```

10. 刺进数据： ```sql INSERT INTO table_name VALUES ; ```

11. 创立表： ```sql CREATE TABLE table_name ; ```

12. 创立索引： ```sql CREATE INDEX index_name ON table_name ; ```

13. 创立视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

14. 创立序列： ```sql CREATE SEQUENCE sequence_name START WITH 1 INCREMENT BY 1; ```

15. 创立近义词： ```sql CREATE SYNONYM synonym_name FOR table_name; ```

16. 创立用户： ```sql CREATE USER username IDENTIFIED BY password; ```

17. 颁发权限： ```sql GRANT privilege ON object_name TO username; ```

18. 收回权限： ```sql REVOKE privilege ON object_name FROM username; ```

19. 创立人物： ```sql CREATE ROLE role_name; ```

20. 人物授权： ```sql GRANT role_name TO username; ```

21. 人物收回： ```sql REVOKE role_name FROM username; ```

22. 创立触发器： ```sql CREATE TRIGGER trigger_name BEFORE/AFTER INSERT/UPDATE/DELETE ON table_name FOR EACH ROW BEGIN trigger body END; ```

23. 创立存储进程： ```sql CREATE PROCEDURE procedure_name AS BEGIN procedure body END; ```

24. 创立函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

25. 创立包： ```sql CREATE PACKAGE package_name AS package specification END; ```

26. 创立包体： ```sql CREATE PACKAGE BODY package_name AS package body END; ```

27. 创立数据库 ```sql CREATE DATABASE LINK link_name CONNECT TO username IDENTIFIED BY password USING 'database_name'; ```

28. 创立物化视图： ```sql CREATE MATERIALIZED VIEW view_name REFRESH COMPLETE ON DEMAND AS SELECT FROM table_name; ```

29. 创立物化视图日志： ```sql CREATE MATERIALIZED VIEW LOG ON table_name WITH ROWID; ```

30. 创立作业： ```sql BEGIN DBMS_SCHEDULER.CREATE_JOB ; END; ```

31. 创立目录： ```sql CREATE DIRECTORY directory_name AS '/path/to/directory'; ```

32. 创立外部表： ```sql CREATE TABLE external_table_name ORGANIZATION EXTERNAL LOCATION qwe2; ```

33. 创立维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

34. 创立等级联系： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

35. 创立等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

36. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

37. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

38. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

39. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

41. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

42. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

43. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

44. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

45. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

46. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

47. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

49. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

50. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

51. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

52. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

53. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

54. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

55. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

57. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

58. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

59. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

60. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

61. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

62. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

63. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

65. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

66. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

67. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

68. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

69. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

70. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

71. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

73. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

74. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

75. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

76. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

77. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

78. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

79. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

81. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

82. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

83. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

84. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

85. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

86. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

87. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

89. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

90. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

91. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

92. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

93. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

94. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

95. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

97. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

98. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

99. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

100. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

101. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

102. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

103. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

105. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

106. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

107. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

108. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

109. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

110. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

111. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name GROUP BY column_name; ```

6. 衔接查询： ```sql SELECT FROM table1 JOIN table2 ON table1.column_name = table2.column_name; ```

7. 子查询： ```sql SELECT FROM table_name WHERE column_name IN ; ```

8. 更新数据： ```sql UPDATE table_name SET column_name = value WHERE condition; ```

9. 删去数据： ```sql DELETE FROM table_name WHERE condition; ```

10. 刺进数据： ```sql INSERT INTO table_name VALUES ; ```

11. 创立表： ```sql CREATE TABLE table_name ; ```

12. 创立索引： ```sql CREATE INDEX index_name ON table_name ; ```

13. 创立视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

14. 创立序列： ```sql CREATE SEQUENCE sequence_name START WITH 1 INCREMENT BY 1; ```

15. 创立近义词： ```sql CREATE SYNONYM synonym_name FOR table_name; ```

16. 创立用户： ```sql CREATE USER username IDENTIFIED BY password; ```

17. 颁发权限： ```sql GRANT privilege ON object_name TO username; ```

18. 收回权限： ```sql REVOKE privilege ON object_name FROM username; ```

19. 创立人物： ```sql CREATE ROLE role_name; ```

20. 人物授权： ```sql GRANT role_name TO username; ```

21. 人物收回： ```sql REVOKE role_name FROM username; ```

22. 创立触发器： ```sql CREATE TRIGGER trigger_name BEFORE/AFTER INSERT/UPDATE/DELETE ON table_name FOR EACH ROW BEGIN trigger body END; ```

23. 创立存储进程： ```sql CREATE PROCEDURE procedure_name AS BEGIN procedure body END; ```

24. 创立函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

25. 创立包： ```sql CREATE PACKAGE package_name AS package specification END; ```

26. 创立包体： ```sql CREATE PACKAGE BODY package_name AS package body END; ```

27. 创立数据库 ```sql CREATE DATABASE LINK link_name CONNECT TO username IDENTIFIED BY password USING 'database_name'; ```

28. 创立物化视图： ```sql CREATE MATERIALIZED VIEW view_name REFRESH COMPLETE ON DEMAND AS SELECT FROM table_name; ```

29. 创立物化视图日志： ```sql CREATE MATERIALIZED VIEW LOG ON table_name WITH ROWID; ```

30. 创立作业： ```sql BEGIN DBMS_SCHEDULER.CREATE_JOB ; END; ```

31. 创立目录： ```sql CREATE DIRECTORY directory_name AS '/path/to/directory'; ```

32. 创立外部表： ```sql CREATE TABLE external_table_name ORGANIZATION EXTERNAL LOCATION qwe2; ```

33. 创立维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

34. 创立等级联系： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

35. 创立等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

36. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

37. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

38. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

39. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

41. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

42. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

43. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

44. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

45. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

46. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

47. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

49. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

50. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

51. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

52. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

53. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

54. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

55. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

57. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

58. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

59. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name ; ```

60. 创立剖析函数： ```sql CREATE FUNCTION function_name RETURN datatype AS BEGIN function body RETURN value; END; ```

61. 创立剖析视图： ```sql CREATE VIEW view_name AS SELECT FROM table_name; ```

62. 创立剖析窗口函数： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

63. 创立剖析查询： ```sql SELECT column_name, ANALYTIC_FUNCTION OVER FROM table_name; ```

65. 创立剖析维度： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name; ```

66. 创立剖析等级： ```sql CREATE DIMENSION dimension_name LEVEL level_name IS column_name RELATIVE LEVELS ; ```

67. 创立剖析等级层次： ```sql CREATE DIMENSION dimension_name HIERARCHY hierarchy_name qwe1 level_name1,

Oracle数据库查询技巧与优化战略

Oracle数据库作为全球最盛行的联系型数据库之一，其强壮的查询功用是数据库办理者和开发者日常作业中不可或缺的部分。本文将介绍一些Oracle数据库查询的技巧和优化战略，帮助您更高效地处理数据。

一、Oracle查询根底

在开端深入探讨查询优化之前，咱们先回忆一下Oracle数据库查询的根底知识。

1.1 数据类型

Oracle数据库支撑多种数据类型，包括数字、字符、日期/时刻、布尔值等。了解并正确运用这些数据类型关于编写高效的查询至关重要。

1.2 联系运算符

联系运算符如等于（=）、不等于（）、大于（>）、小于（1.3 逻辑运算符

逻辑运算符如AND、OR、NOT等用于组合多个条件。

二、Oracle查询技巧

2.1 运用索引

索引是进步查询功能的要害。经过在常常用于查询条件的列上创立索引，能够明显削减查询所需的时刻。

2.2 运用LIKE查询

LIKE查询用于匹配包括特定形式的字符串。运用通配符（%和_）能够更灵敏地进行查找。

2.3 运用BETWEEN查询

BETWEEN查询用于查找指定范围内的数据。它能够简化查询句子，进步可读性。

2.4 运用聚合函数

聚合函数如SUM、AVG、COUNT等用于对一组数据进行核算。它们在处理很多数据时十分有用。

三、Oracle查询优化战略

3.1 剖析履行计划

履行计划是Oracle数据库在履行查询时生成的内部作业流程。经过剖析履行计划，您能够了解查询的履行方法，并找出潜在的瓶颈。

3.2 防止全表扫描

全表扫描是查询功能的杀手。经过运用索引和恰当的查询条件，能够防止全表扫描，然后进步查询速度。

3.3 优化查询句子

防止运用SELECT ；

运用别号简化查询句子；

防止在WHERE子句中运用函数；

运用JOIN替代子查询。

3.4 运用分区表

分区表能够将大型表分解为更小的、更易于办理的部分。这有助于进步查询功能，并简化数据办理。