reference: http://www.tutorialspoint.com/sql important: constrains: SQL constraints are used to specify rules for the data in a table. If there is any violation between the constraint and the data action‚ the action is aborted by the constraint. In SQL‚ we have the following constraints: NOT NULL - Indicates that a column cannot store NULL value UNIQUE - Ensures that each rows for a column must have a unique value PRIMARY KEY - A combination of a NOT NULL and UNIQUE. Ensures that
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The Appeal Abolitionist David Walker published the pamphlet‚ Appeal‚ which encouraged enslaved men and women to rebel against their white owners for their freedom. This pamphlet urged emancipation of all slaves in the United States and argued the idea of colonization. Walker’s audience in Appeal was intended for all enslaved men and women in the United States and around the world. Walker’s pamphlet Appeal caused a major controversy within slave owners and slaves but also inspired many future leaders
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Synthesis Essay These essays disclose the issues concerning grades and how they are perceived and rewarded by teachers. With that being broken down‚ I realize I go through my classes expecting great grades. Both authors explained that grade inflation is the cause of both high school and college students thinking the same way. The idea of changing the grade scale was for "the benefit" of the students but‚ I think it is causing the students to slack off. When the students are not being challenged
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TASKBAR In the graphical user interface (GUI) for a computer operating system or application‚ a taskbar is a visual device on the desktop that typically shows the user which applications (tasks) are currently active and running. Combined window management and program launching As noted above‚ the Windows 7 taskbar combines two previously separate bits of functionality: Open window management and program launching/file opening. Prior to Windows 7‚ the taskbar was generally used only to manage open
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Introduction The American Chemical Society databases were investigated through Scifinder Scholar Version X to find any information about Butyl 2-Cyano-(3‚5 dichloro-phenyl)-2-propenoate. There was no previous information present. Then‚ the microscale synthesis and characterization of Butyl 2-Cyano-(3‚5 dichloro-phenyl)-2-propenoate was conducted with the base catalyzed Knoevengael condensation of the butyl cyanoacetate and corresponding aldehyde (gkharas/235_14F/235_14F_Lab_2.pdf) and analysis. The elemental
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Protein Synthesis Worksheet 1. 2. a. Protein synthesis began in the nucleus. b. Chromatin is a diffuse mass located in the nucleus where genetic material is found. c. A gene is a sequence of nucleotides‚ it is important because they form the template and these templates are used for synthesizing proteins. 3. a. Transcription is the first step of protein synthesis it uses a sequence of DNA nucleotides to produce a sequence of RNA nucleotide. b. RNA polymerase bonds to RNA nucleotides together
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Synthesis of Isopentyl Acetate Abstract The purpose of this experiment was to produce isopentyl acetate‚ banana oil. Acetic acid and isoamyl alcohol were used to synthesize isopentyl acetate. The techniques used for the separation and purification of isopentyl acetate were reflux‚ liquid-liquid extraction‚ neutralization and distillation. The identification of isopentyl acetate was based on boiling points and an infrared spectrum. This experiment resulted in a 11.68% yield. The reactants
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1/29 Function of nervous system Basically designed to keep you alive Essentially you can adapt to whatever environment you’re in and stay alive Adapt to be able to do behaviors Drugs have direct effect on NS Synaptic transmission Started out neuron centric until about 10 years ago Basically looked at how drugs affect neurons and what role neurons play in behaviors How neurons were communicating with other neurons or other cells in body All drugs changed what was happening at synapse
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21 Basic Tools in Visual Basic 0.6 Control Description Pointer Provides a way to move and resize the controls form PictureBox Displays icons/bitmaps and metafiles. It displays text or acts as a visual container for other controls. TextBox Used to display message and enter text. Frame Serves as a visual and functional container for controls. CommandButton Used to carry out the specified action when the user chooses it. CheckBox Displays a True/False or Yes/No option. OptionButton
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What’s the difference between resistance and resistivity? Resistance is the obstruction offered to the flow of current by a conductor. Resistivity is the obstruction offered to the flow of current by UNIT AREA OF the conductor. So basically‚ resistance is the property of the object (say a copper wire)‚ whereas resistivity is the property of the substance (copper). And so resistance depends upon the properties of the object. Whereas resistivity depends upon the properties of the metal.
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