Common Patterns

SQL operator

Structure:

• Array
  • first element - Symbol that begins from _ - :_nullif
  • arguments
    • columns

[:_count, [:_nullif, :row, [:_params, 'mrgl']]] # TODO: param?
# => ['COUNT(NULLIF(row, $1))', ['mrgl']]

Detailed Operators description.

Columns

Possible structures:

• String
  • if it locted in the Hash with table alias, table alias will be added to it
  • if there is no table alias it will be returned to the builder as it is.
• Symbol - just parsed to string
• Hash
  • key - table alias||name
  • value - columns
• SQL operator
• Sub Query
• Array - holder of any possible structures

['name', {u: ['role', 'u.phone, m.rating', :field]}]
# => 'name, u.role, u.phone, m.rating, u.field'

Detailed Select description

Tables

Possible structures:

• String || Symbol
• SQL operator
• Array
  • if there is no Array inside it will be joined structure.join ' '
  • Array with any tables structure.

['users u', [:_values, ...], [:masters, :m]]
'users u, (VALUES...), masters m'

Conditions

Not finished yet... Column can be described as :u__name => 'u.name' or :name Possible structures:

• String passes as it is
• Hash represent sql = or IN if value is Array. TODO: IS in case of nil or false
  • Symbol - column name
  • Array - only as value! will be placed in querry params ($1).
  • String - will be placed in querry params
• Array
  • first element - Symbol operator representation, by default :and
    • eq - =
    • or, and
    • in
    • not
    • like, ilike
    • reg - ~, reg_i - ~*, reg_f - !~, reg_fi - !~*
  • arguments
• Array - holder of any possible structures

[[:not, 'z = 13'],
 [:or, 'mrgl = 2', 'rgl = 22'],
 [:or, 'rgl = 12', 'zgl = lol']]
# => 'NOT z = 13 AND (mrgl = 2 OR rgl = 22) AND (rgl = 12 OR zgl = lol)'
[{ role: 'manager', id: [0, 1, 153] },
 [:not, [:like, :u__name, 'Aeonax']]]
#=> 'role = $1 AND id IN ($2) AND NOT u.name LIKE $3', ['manager', [0, 1, 153], 'Aeonax']

Sub Query

Possible structures:

• Constructor instance
• Hash with :select value