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Open The Parser Python File in Linux or Windows Idle and run as python parser.py in Linux.

=======> This is the Help Manual for the Relational Algebra <========
	
			Here are the instructions

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1.Selection (Sigma):
	This is used to simulate the select or the sigma operator of relational algebra to select few tuples.
   Syntax : " select/sigma | <relation_name> | on | <conditions> "
	This can also be used recursively,where , you need to write the name of expression instead of the <relation_name> field
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2.Project (Pi):
	Return a new relation with a heading restricted to the given fields or like the pi operator of relational algebra to project few columns.
   Syntax : " project/pi | <list_of_attributes> | from | <relation_name> "
	This can also be used recursively,where , you need to write the name of expression instead of the <relation_name> field 
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3.Rename (Rho):
	This is used to rename some fields in this relation, like the rho operator in relational algebra.
    
	Syntax : " rename/rho | <old_relation_name> | to | <new_relation_name> | <new_attributes> "  
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