1. One or more non-transitory computer readable storage mediums storing one or more sequences of instructions, which when executed by one or more processors, causes: converting a SQL expression into an S-expression tabular structure, wherein said S-expression comprises a nested list; generating a function table based on said S-expression tabular structure, wherein said function table comprises a plurality of functions associated with said S expression tabular structure tabulated against at least one of a function name, a derived column and a derived table; generating an argument table based on said S-expression tabular structure, wherein said argument table comprises a plurality of arguments associated with said S expression tabular structure tabulated against at least one of an argument type, a function identification, a computed from function, a reference to entity or a literal value; and converting at least one function associated with said S-expression tabular structure to a pre-determined language, based on a language map of said pre-determined language and said function table and said argument table.
6. The one or more non-transitory computer readable storage mediums of claim 1 , wherein converting said SQL expression into an S-expression tabular structure comprises: retrieving one or more keywords and one or more arguments associated with said SQL expression; generating a tabular representation of said one or more keywords and said one or more arguments, wherein said tabular representation comprises said one or more keywords and said one or more arguments arranged at a plurality of levels comprising a lowest outermost level and a highest innermost level, based on a level of said one or more keywords and said one or more arguments in a syntax of said SQL expression; and generating said S-expression tabular structure by traversing said tabular representation and grouping one or more arguments subsequent to a keyword at a level from among said plurality of levels and prior to a subsequent keyword at said level or a subsequent lower level from among said plurality of levels, wherein said grouped one or more arguments are represented as arguments of said keyword nested within a pair of parenthesis following said keyword, wherein said keyword is represented as a function with said one or more arguments, and wherein upon said subsequent keyword being at said subsequent lower level, said keyword along with said nested arguments of said level are nested within another pair of parenthesis.