triggers referential integrity and commitment control
Data Integrity and Advanced Query Technique
Ngày tải lên :
25/08/2012, 09:00
... riêng sau liên kết với cột table CHECK constraint thuộc tính table nên tạo với lệnh CREATE TABLE Triggers : Một loại stored procedure đặc biệt thực thi cách tự động table Update, Insert, hay Delete ... hàng bán tổng số hàng hóa kho phải giảm xuống (-1) chẳng hạn ta dùng trigger để đảm bảo chuyện Triggers bàn kỹ sau Indexes : bàn đến nói Indexes Constraints Constraints thuộc tính (property) ... TABLE Table1 (Col1 INT PRIMARY KEY, Col2 INT CONSTRAINT limit_amount 1000), CHECK (Col2 BETWEEN AND Col3 VARCHAR(30) ) Trong ví dụ ta giới hạn giá trị chấp nhận cột Col2 từ đến 1000 Ví dụ sau...
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ESTROGENIC ACTIVITY LEVEL OF NAKDONG RIVER BASIN AND ITS CONTROL BY WATER TREATMENT PROCESSES
Ngày tải lên :
05/09/2013, 08:40
... Andong Daegu Busan Andong Waegwan Gangjung Daegu Gumho Riv Goryung Brd Hwang Riv Jeokpo Brd Namji RESULTS AND DISCUSSION Nam Riv Fig shows the sampling points along of Nakdong River in May, and ... excluding Namji and Nam River in May 2002 Yeast Two-hybrid assay and ELISA method for Nakdong River water revealed that estrogenic substances and activity is distributed over the whole middle and downstream ... E2, E1, and APE concentrations for the secondary treatment water and for ozone treatment water in the sewage treatment plants than for the inflow water (Figure3 and Table 2) In domestic and industrial...
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Multi criteria analysis in environmental management: Selecting the best stormwater erosion and sediment control measure in Malaysian construction sites
Ngày tải lên :
05/09/2013, 16:11
... III = Seeding and planting, IV = Geotextiles and mats, V = Terracing Based on equation above, the recommended best control measure for controlling erosion due to land clearing and when the area ... addition to flow control and pollution removal The application of BMPs facilities involves a variety of stakeholders in both the public and private arenas and therefore their development and design ... Environmental TSS Control Removal cost Material availability Social and community Public health & safety risk Turbidity Control Risk of BMP fail Stakeholder acceptability Figure Erosion and sediment control...
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Data Integrity and Advanced Query Technique
Ngày tải lên :
06/10/2013, 17:20
... CREATE TABLE Table1 (Col1 INT PRIMARY KEY, Col2 INT CONSTRAINT limit_amount CHECK (Col2 BETWEEN AND 1000), Col3 VARCHAR(30) ) Trong ví dụ ta giới hạn giá trị chấp nhận cột Col2 từ đến 1000 Ví ... (Col1 INT PRIMARY KEY, Col2 INT, Col3 VARCHAR(30), CONSTRAINT limit_amount CHECK (Col2 BETWEEN AND 1000) ) Tương tự Foreign Key Constraint ta cần disable Check Constraint trường hợp Insert hay ... EmployeeNames SELECT FirstName, LastName FROM Employers Chú ý chữ "Value" câu Insert The GROUP BY and HAVING Clauses GROUP BY dùng để tạo giá trị tổng (aggregate values) cho hàng kết select Chỉ...
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Pro .NET 2.0 Windows Forms and Custom Controls in C#
Ngày tải lên :
19/10/2013, 21:15
... custom controls you can create and see how to set up a custom control project You’ll then continue to create user controls, which combine other controls into reusable groups (Chapter 10); derived controls, ... child controls In other words, controls are linked together by containment using the Controls collection Because every control is a class that derives from System.Windows.Forms .Control, every control ... to enhance NET controls and build your own In this book, you’ll learn key techniques to extend existing controls and create your own from scratch You’ll even learn how to draw controls from scratch...
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Congestion and Error Control in Overlay Networks
Ngày tải lên :
26/10/2013, 17:15
... Link Control (DLC) achieves this through the flow control mechanism There are two approaches for doing flow control: Stop -and- Wait flow control Sliding-Window flow control In the Stop -and- Wait flow control ... protocols 2.3.1 Stop -and- Wait ARQ The Stop -and- Wait ARQ error control mechanism is based on the Stop -and- Wait flow control In its simplest form, the sender transmits a frame and it waits for ACK ... for congestion and error control are also described 2.2 Congestion Control Mechanisms A simple definition of network congestion can be as follows: Chapter Congestion and Error Control in Unicast...
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SIMULATION AND SPEED CONTROL OF INDUCTION MOTOR DRIVES
Ngày tải lên :
18/12/2013, 22:06
... MATLAB Simulink and the effects of various parameters such as rotor and stator resistances and inductances were analysed Also different control algorithms such as P, PI and PID control were studied ... 38 4.3.2 Open Loop V/f speed control method using PI controller 42 4.3.3 Closed Loop V/f speed control method using PI controller 44 4.4 Vector Control Method 47 ... MATLAB SIMULINK and the rotor and stator currents, speed, electromagnetic torque and the Torque-Speed characteristics were observed with different values of rotor and stator resistances and impedances...
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