Sawzall

As a query language, Sawzall is a type safe scripting language. Because their own Sawzall to deal with a lot of problems, so to accomplish the same function code simplifies the very much - with MapReduce C + + code compared to simplify the 10 times more than.

Sawzall syntax and expression a big part of that is from the C transposed; including for loop, while loop, if statement, and C inside very similar. Define the part from the traditional Pascal model:

I: int a simple integer declaration #;

I: int = 0; a declaration with an initial value #;

Basic types include integer ( int ), is a 64 bit unsigned value; floating point ( float ), is a double precision IEEE floating point; and the very similar integers time and fingerprint. Time is a millisecond time, and functions including the type conversion and operation. Fingerprint is an operative definition of the hash value, can be easily through the establishment of data fingerprint to construct the aggregator index.

At the same time, Sawzall also has two basic array types: bytes, similar to the C unsigned char string, string array; used to store UNICODE string. In Sawzall without" character" type; byte array and string is an essential element of int, and although the capacity of int than byte string or basic elements be greater.

Composite type, maps ( this document can be overloaded concept ), tuples. The array is used as an index to retrieve, maps is a combination of an array or a Python dictionary types, can use any type of retrieval, can be required to establish the disordered index. The last tuples of arbitrary groups, similar to C or PASCAL structure type. Any type can have a formal name.