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readme.txt
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readme.txt
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Query:
Select - S[predicate](relation)
Project - P[column list](relation) columns in column list are seperated by comma
Rename - R[new relation name(new column names)](old relation name)
Union - U[relation_1](relation_2)
Intersection - I[relation_1](relation_2)
Set Difference - D[relation_1](relation_2) relation_1 - relation_2
Cartesian Product - C[relation_1](relation_2)
Exit - exit
Note:
-> In predicate, constants (either string or integer) must be enclosed by ' '
-> Queries are case insensitive (both table names and column names)
-> Use * in project query to project all the columns of a table
-> Table and its columns can be renamed independently. But to rename a column, all the columns must be
renamed. i.e., no.of new column names = total no.of columns in the table, or 0