1 | #include <DataTypes/DataTypeString.h> |
---|---|
2 | #include <Functions/FunctionFactory.h> |
3 | #include <Functions/FunctionStringOrArrayToT.h> |
4 | |
5 | |
6 | namespace DB |
7 | { |
8 | |
9 | |
10 | /** Calculates the length of a string in bytes. |
11 | */ |
12 | struct LengthImpl |
13 | { |
14 | static constexpr auto is_fixed_to_constant = true; |
15 | |
16 | static void vector(const ColumnString::Chars & /*data*/, const ColumnString::Offsets & offsets, PaddedPODArray<UInt64> & res) |
17 | { |
18 | size_t size = offsets.size(); |
19 | for (size_t i = 0; i < size; ++i) |
20 | res[i] = offsets[i] - 1 - offsets[i - 1]; |
21 | } |
22 | |
23 | static void vector_fixed_to_constant(const ColumnString::Chars & /*data*/, size_t n, UInt64 & res) |
24 | { |
25 | res = n; |
26 | } |
27 | |
28 | static void vector_fixed_to_vector(const ColumnString::Chars & /*data*/, size_t /*n*/, PaddedPODArray<UInt64> & /*res*/) |
29 | { |
30 | } |
31 | |
32 | static void array(const ColumnString::Offsets & offsets, PaddedPODArray<UInt64> & res) |
33 | { |
34 | size_t size = offsets.size(); |
35 | for (size_t i = 0; i < size; ++i) |
36 | res[i] = offsets[i] - offsets[i - 1]; |
37 | } |
38 | }; |
39 | |
40 | |
41 | struct NameLength |
42 | { |
43 | static constexpr auto name = "length"; |
44 | }; |
45 | |
46 | using FunctionLength = FunctionStringOrArrayToT<LengthImpl, NameLength, UInt64>; |
47 | |
48 | void registerFunctionLength(FunctionFactory & factory) |
49 | { |
50 | factory.registerFunction<FunctionLength>(FunctionFactory::CaseInsensitive); |
51 | } |
52 | |
53 | } |
54 |