PgQuery

A libpg_query wrapper written in elixir.

Useful for parsing postgresql queries.

Usage

Fingerprint

Fingerprints queries will ignoring formatting and concrete values.

iex> PgQuery.fingerprint_query("SELECT count(*) from users where age > 50") 
{:ok, "02dd673649193e38c3e5afb638f51614fee858ab1e"}
iex> PgQuery.fingerprint_query("SELECT count(*) from users where age < 50") 
{:ok, "02dd673649193e38c3e5afb638f51614fee858ab1e"}
iex> PgQuery.fingerprint_query("SELECT 1 + 2")               
{:ok, "025a33db2ae7cbfce37fa78c34b32e75b376eb6d16"}

Query parsing

iex> PgQuery.parse_query("SELECT name, age from users")
{:ok,
 [
   %{
     "RawStmt" => %{
       "stmt" => %{
         "SelectStmt" => %{
           "fromClause" => [
             %{
               "RangeVar" => %{
                 "inh" => true,
                 "location" => 22,
                 "relname" => "users",
                 "relpersistence" => "p"
               }
             }
           ],
           "op" => 0,
           "targetList" => [
             %{
               "ResTarget" => %{
                 "location" => 7,
                 "val" => %{
                   "ColumnRef" => %{
                     "fields" => [%{"String" => %{"str" => "name"}}],
                     "location" => 7
                   }
                 }
               }
             },
             %{
               "ResTarget" => %{
                 "location" => 13,
                 "val" => %{
                   "ColumnRef" => %{
                     "fields" => [%{"String" => %{"str" => "age"}}],
                     "location" => 13
                   }
                 }
               }
             }
           ]
         }
       }
     }
   }
 ]}

Installation

If available in Hex, the package can be installed by adding pg_query to your list of dependencies in mix.exs:

def deps do
  [
    {:pg_query, "~> 0.1.0"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/pg_query.