A sequence of boolean expressions in parsed SQL is difficult to walk

[jessestimpson]

I'm attempting to walk the AST returned by SQL.Parser, and I'm finding the structure of a sequence of boolean expressions in a where clause to be counter-intuitive.

SQL to demonstrate: select id from events where timestamp > 1 and timestamp < 4;

Here's the current structure of the 'where' after Lexing and Parsing (metadata omitted for clarity)

{:where, _,
 [ {:<, _, [ {:and, _, [ {:>, _, [ {:timestamp, _, []}, {:numeric. _, [[], 49]} ]}, {:timestamp, _, []} ]}, {:numeric, _, [[], 52]} ]} ]
},

The AST above reads as:

((timestamp > 1) and timestamp) < 4

My expectation:

{:where, _,
 [ {:and, _ [ {:>, _, [ {:timestamp, _, []}, {:numeric, _, [[], 49]} ]}, {:<, _, [ {:timestamp, _, []}, {:numeric, _, [[], 52]} ]} ] } ]
}

This AST reads as:

(timestamp > 1) and (timestamp < 4)

Am I looking at the AST wrong?

[Schultzer]

Your expectations are correct, and that is a bug in the parser.

[Schultzer]

This should be fixed on main.

iex(2)> ~SQL[select id from events where timestamp > 1 and timestamp < 4;].tokens
[
  {:colon, [type: :expression, line: 0, column: 60, file: "iex"],
   [
     {:select, [keyword: :reserved, line: 0, column: 6, file: "iex"],
      [
        {:ident, [size: 2, type: :literal, line: 0, column: 9, file: "iex"],
         [[[], 105], 100]}
      ]},
     {:from, [keyword: :reserved, line: 0, column: 14, file: "iex"],
      [
        {:ident, [size: 6, type: :literal, line: 0, column: 21, file: "iex"],
         [[[[[[[], 101], 118], 101], 110], 116], 115]}
      ]},
     {:where, [keyword: :reserved, line: 0, column: 27, file: "iex"],
      [
        {:and, [keyword: :reserved, line: 0, column: 45, file: "iex"],
         [
           {:>, [line: 0, column: 39, file: "iex"],
            [
              {:timestamp,
               [keyword: :reserved, line: 0, column: 37, file: "iex"], []},
              {:numeric,
               [
                 sign: 0,
                 whole: 1,
                 fractional: 0,
                 type: :literal,
                 line: 0,
                 column: 41,
                 file: "iex"
               ], [[], 49]}
            ]},
           {:<, [line: 0, column: 57, file: "iex"],
            [
              {:timestamp,
               [keyword: :reserved, line: 0, column: 55, file: "iex"], []},
              {:numeric,
               [
                 sign: 0,
                 whole: 1,
                 fractional: 0,
                 type: :literal,
                 line: 0,
                 column: 59,
                 file: "iex"
               ], [[], 52]}
            ]}
         ]}
      ]}
   ]},
  []
]

[jessestimpson]

Excellent, thank you. I was able to remove my hack, much cleaner now!