數(shù)據(jù)庫系統(tǒng)工程師考試2025數(shù)據(jù)庫系統(tǒng)SQL優(yōu)化與執(zhí)行試題集考試時間：______分鐘總分：______分姓名：______一、SQL語句優(yōu)化要求：請對以下SQL語句進(jìn)行優(yōu)化，并解釋優(yōu)化原因。1.原始SQL語句：```SELECT*FROMEmployeesWHEREDepartmentID=10;```優(yōu)化后的SQL語句：```SELECTEmployeeID,Name,DepartmentIDFROMEmployeesWHEREDepartmentID=10;```優(yōu)化原因：______2.原始SQL語句：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化后的SQL語句：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化原因：______3.原始SQL語句：```SELECT*FROMProductsWHERECategoryID=2ANDPrice>100;```優(yōu)化后的SQL語句：```SELECTProductID,Name,CategoryID,PriceFROMProductsWHERECategoryID=2ANDPrice>100;```優(yōu)化原因：______4.原始SQL語句：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化后的SQL語句：```SELECTCustomerID,Name,CityFROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化原因：______5.原始SQL語句：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化后的SQL語句：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化原因：______6.原始SQL語句：```SELECT*FROMEmployeesWHEREDepartmentID=10ANDSalary>50000;```優(yōu)化后的SQL語句：```SELECTEmployeeID,Name,DepartmentID,SalaryFROMEmployeesWHEREDepartmentID=10ANDSalary>50000;```優(yōu)化原因：______7.原始SQL語句：```SELECT*FROMProductsWHERECategoryID=2ANDPriceBETWEEN100AND200;```優(yōu)化后的SQL語句：```SELECTProductID,Name,CategoryID,PriceFROMProductsWHERECategoryID=2ANDPriceBETWEEN100AND200;```優(yōu)化原因：______8.原始SQL語句：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化后的SQL語句：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化原因：______9.原始SQL語句：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化后的SQL語句：```SELECTCustomerID,Name,CityFROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化原因：______10.原始SQL語句：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化后的SQL語句：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化原因：______二、SQL查詢優(yōu)化要求：請對以下SQL查詢進(jìn)行優(yōu)化，并解釋優(yōu)化原因。1.原始SQL查詢：```SELECT*FROMEmployeesWHEREDepartmentID=10;```優(yōu)化后的SQL查詢：```SELECTEmployeeID,Name,DepartmentIDFROMEmployeesWHEREDepartmentID=10;```優(yōu)化原因：______2.原始SQL查詢：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化后的SQL查詢：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化原因：______3.原始SQL查詢：```SELECT*FROMProductsWHERECategoryID=2ANDPrice>100;```優(yōu)化后的SQL查詢：```SELECTProductID,Name,CategoryID,PriceFROMProductsWHERECategoryID=2ANDPrice>100;```優(yōu)化原因：______4.原始SQL查詢：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化后的SQL查詢：```SELECTCustomerID,Name,CityFROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化原因：______5.原始SQL查詢：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化后的SQL查詢：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化原因：______6.原始SQL查詢：```SELECT*FROMEmployeesWHEREDepartmentID=10ANDSalary>50000;```優(yōu)化后的SQL查詢：```SELECTEmployeeID,Name,DepartmentID,SalaryFROMEmployeesWHEREDepartmentID=10ANDSalary>50000;```優(yōu)化原因：______7.原始SQL查詢：```SELECT*FROMProductsWHERECategoryID=2ANDPriceBETWEEN100AND200;```優(yōu)化后的SQL查詢：```SELECTProductID,Name,CategoryID,PriceFROMProductsWHERECategoryID=2ANDPriceBETWEEN100AND200;```優(yōu)化原因：______8.原始SQL查詢：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化后的SQL查詢：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```優(yōu)化原因：______9.原始SQL查詢：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化后的SQL查詢：```SELECTCustomerID,Name,CityFROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```優(yōu)化原因：______10.原始SQL查詢：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化后的SQL查詢：```SELECTOrderID,CustomerID,OrderDateFROMOrdersWHEREOrderDate='2022-01-01';```優(yōu)化原因：______三、SQL查詢執(zhí)行計(jì)劃要求：請根據(jù)以下SQL查詢，分析其執(zhí)行計(jì)劃，并解釋執(zhí)行計(jì)劃中的關(guān)鍵信息。1.SQL查詢：```SELECT*FROMEmployeesWHEREDepartmentID=10;```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Employees|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______2.SQL查詢：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Orders|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______3.SQL查詢：```SELECT*FROMProductsWHERECategoryID=2ANDPrice>100;```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Products|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______4.SQL查詢：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Customers|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______5.SQL查詢：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Orders|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______6.SQL查詢：```SELECT*FROMEmployeesWHEREDepartmentID=10ANDSalary>50000;```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Employees|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______7.SQL查詢：```SELECT*FROMProductsWHERECategoryID=2ANDPriceBETWEEN100AND200;```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Products|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______8.SQL查詢：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Orders|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______9.SQL查詢：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Customers|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______10.SQL查詢：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```執(zhí)行計(jì)劃：```+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|id|select_type|table|partitions|type|possible_keys|key|key_len|ref|rows|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+|1|SIMPLE|Orders|NULL|eq_ref|PRIMARY|PRIMARY|4|const|1|+----+-------------+------+------------+------+----------------+----------------+---------+----------------------+----------------+```關(guān)鍵信息：______四、SQL索引優(yōu)化要求：請針對以下SQL查詢，分析其索引優(yōu)化策略，并說明選擇該策略的原因。1.SQL查詢：```SELECT*FROMEmployeesWHEREDepartmentID=10ANDSalary>50000;```索引優(yōu)化策略：```CREATEINDEXidx_department_salaryONEmployees(DepartmentID,Salary);```選擇該策略的原因：______2.SQL查詢：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```索引優(yōu)化策略：```CREATEINDEXidx_customer_orderdateONOrders(CustomerID,OrderDate);```選擇該策略的原因：______3.SQL查詢：```SELECT*FROMProductsWHERECategoryID=2ANDPriceBETWEEN100AND200;```索引優(yōu)化策略：```CREATEINDEXidx_category_priceONProducts(CategoryID,Price);```選擇該策略的原因：______4.SQL查詢：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```索引優(yōu)化策略：```CREATEINDEXidx_cityONCustomers(City);```選擇該策略的原因：______5.SQL查詢：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```索引優(yōu)化策略：```CREATEINDEXidx_orderdateONOrders(OrderDate);```選擇該策略的原因：______五、SQL性能分析要求：請根據(jù)以下SQL查詢，分析其性能瓶頸，并提出相應(yīng)的優(yōu)化建議。1.SQL查詢：```SELECT*FROMEmployeesWHEREDepartmentID=10;```性能瓶頸：```-表Employees數(shù)據(jù)量大，查詢時掃描全表；-缺少合適的索引；```優(yōu)化建議：```-在DepartmentID上創(chuàng)建索引；-分析查詢頻率，考慮是否使用緩存；```2.SQL查詢：```SELECT*FROMOrdersWHERECustomerID=5ANDOrderDateBETWEEN'2022-01-01'AND'2022-12-31';```性能瓶頸：```-表Orders數(shù)據(jù)量大，查詢時掃描全表；-缺少合適的索引；```優(yōu)化建議：```-在CustomerID和OrderDate上創(chuàng)建復(fù)合索引；-分析查詢頻率，考慮是否使用緩存；```3.SQL查詢：```SELECT*FROMProductsWHERECategoryID=2ANDPrice>100;```性能瓶頸：```-表Products數(shù)據(jù)量大，查詢時掃描全表；-缺少合適的索引；```優(yōu)化建議：```-在CategoryID和Price上創(chuàng)建復(fù)合索引；-分析查詢頻率，考慮是否使用緩存；```4.SQL查詢：```SELECT*FROMCustomersWHERECity='NewYork'ORCity='LosAngeles';```性能瓶頸：```-表Customers數(shù)據(jù)量大，查詢時掃描全表；-缺少合適的索引；```優(yōu)化建議：```-在City上創(chuàng)建索引；-分析查詢頻率，考慮是否使用緩存；```5.SQL查詢：```SELECT*FROMOrdersWHEREOrderDate='2022-01-01';```性能瓶頸：```-表Orders數(shù)據(jù)量大，查詢時掃描全表；-缺少合適的索引；```優(yōu)化建議：```-在OrderDate上創(chuàng)建索引；-分析查詢頻率，考慮是否使用緩存；```六、SQL事務(wù)管理要求：請根據(jù)以下SQL事務(wù)場景，分析其事務(wù)特性，并說明如何保證事務(wù)的ACID屬性。1.事務(wù)場景：```-用戶A從賬戶中轉(zhuǎn)賬給用戶B，轉(zhuǎn)賬金額為1000元；-同時更新用戶A和B的賬戶余額；```事務(wù)特性：```-原子性：轉(zhuǎn)賬和賬戶余額更新操作必須同時成功或同時失?。?一致性：轉(zhuǎn)賬后，用戶A和B的賬戶余額必須符合預(yù)期；-隔離性：用戶A的轉(zhuǎn)賬操作不會影響其他用戶的操作；-持久性：一旦事務(wù)提交，轉(zhuǎn)賬和賬戶余額更新操作的結(jié)果必須永久保存；```保證ACID屬性的方法：```-使用事務(wù)控制語句（BEGINTRANSACTION,COMMIT,ROLLBACK）；-設(shè)置隔離級別，避免臟讀、不可重復(fù)讀和幻讀；-使用鎖機(jī)制，保證事務(wù)的原子性和一致性；```本次試卷答案如下：一、SQL語句優(yōu)化1.優(yōu)化原因：原始SQL語句