Use search paths in path extractors - Amazon Athena

Use search paths in path extractors

The SerDe property syntax for path extractor contains a <path_extractor_expression>:

"ion.<column_name>.path_extractor" = "<path_extractor_expression>"

You can use the <path_extractor_expression> to specify a search path that parses the Amazon Ion document and finds matching data. The search path is enclosed in parenthesis and can contain one or more of the following components separated by spaces.

  • Wild card – Matches all values.

  • Index – Matches the value at the specified numerical index. Indices are zero-based.

  • Text – Matches all values whose field names match are equivalent to the specified text.

  • Annotations – Matches values specified by a wrapped path component that has the annotations specified.

The following example shows an Amazon Ion document and some example search paths.

-- Amazon Ion document
{
    foo: ["foo1", "foo2"] ,
    bar: "myBarValue", 
    bar: A::"annotatedValue"
}

-- Example search paths
(foo 0)       # matches "foo1"
(1)           # matches "myBarValue"
(*)           # matches ["foo1", "foo2"], "myBarValue" and A::"annotatedValue"
()            # matches {foo: ["foo1", "foo2"] , bar: "myBarValue", bar: A::"annotatedValue"}
(bar)         # matches "myBarValue" and A::"annotatedValue"
(A::bar)      # matches A::"annotatedValue"