Database.Persist.Sql.Raw.QQ

Analoguous to rawQuery

Analoguous to rawQueryRes

QuasiQuoter for performing raw sql queries, analoguous to rawSql

This and the following are convenient QuasiQuoters to perform raw SQL queries. They each follow the same pattern and are analogous to the similarly named raw functions. Neither the quoted function's behaviour, nor it's return value is altered during the translation and all documentation provided with it holds.

These QuasiQuoters perform a simple substitution on the query text, that allows value substitutions, table name substitutions as well as column name substitutions.

Here is a small example:

Given the following simple model:

Category
  rgt Int default=0
  lft Int default=0
  nam Text

We can now execute this raw query:

let lft = 10 :: Int
    rgt = 20 :: Int
    width = rgt - lft
    nams = "first" :| ["second", "third"]
 in [sqlQQ|
      DELETE FROM ^{Category} WHERE @{CategoryLft} BETWEEN #{lft} AND #{rgt};
      UPDATE category SET @{CategoryRgt} = @{CategoryRgt} - #{width} WHERE @{CategoryRgt} > #{rgt};
      UPDATE category SET @{CategoryLft} = @{CategoryLft} - #{width} WHERE @{CategoryLft} > #{rgt};
      SELECT ?? FROM ^{Category} WHERE ^{Category}.@{CategoryNam} IN %{nams};
      INSERT INTO ^{Category}(@{CategoryNam}) VALUES *{Single <$> nams};
    |]

• ^{TableName} looks up the table's name and escapes it

• @{ColumnName} looks up the column's name and properly escapes it

• #{value} inserts the value via the usual parameter substitution mechanism

• %{values} inserts comma separated values (of a NonEmpty list) (since 2.9.1)

• *{rows} inserts a NonEmpty list of tuples for use with a multirow INSERT statement (since 2.9.2)

Analoguous to rawExecute

Analoguous to rawExecuteCount