module Clear::SQL::Query::Pluck
Direct including types
Defined in:
clear/sql/query/pluck.crInstance Method Summary
-
#pluck(fields : Tuple(*T)) forall T
Select specifics columns and return an array of Tuple(*Clear::SQL::Any) containing the columns in the order of the selected arguments:
-
#pluck(*fields)
Select specifics columns and return an array of Tuple(*Clear::SQL::Any) containing the columns in the order of the selected arguments:
-
#pluck(**fields : **T) forall T
Select specifics columns and returns on array of tuple of type of the named tuple passed as parameter:
-
#pluck_col(field : Clear::SQL::Symbolic, type : T.class) forall T
Select a specific column of your SQL query, execute the query and return an array containing this field.
-
#pluck_col(field : Clear::SQL::Symbolic)
Select a specific column of your SQL query, execute the query and return an array containing this field.
Instance Method Detail
Select specifics columns and return an array of Tuple(*Clear::SQL::Any) containing the columns in the order of the selected arguments:
User.query.pluck("first_name", "last_name").each do |(first_name, last_name)|
# ...
end
Select specifics columns and return an array of Tuple(*Clear::SQL::Any) containing the columns in the order of the selected arguments:
User.query.pluck("first_name", "last_name").each do |(first_name, last_name)|
# ...
end
Select specifics columns and returns on array of tuple of type of the named tuple passed as parameter:
User.query.pluck(id: Int64, "UPPER(last_name)": String).each do #...
Select a specific column of your SQL query, execute the query and return an array containing this field.
User.query.pluck_col("id") # [1,2,3,4...]
Note: It returns an array of Clear::SQL::Any
. Therefore, you may want to use #pluck_col(str, Type)
to return
an array of Type
:
User.query.pluck_col("id", Int64)
The field argument is a SQL fragment; it's not escaped (beware SQL injection) and allow call to functions and aggregate methods:
# ...
User.query.pluck_col("CASE WHEN id % 2 = 0 THEN id ELSE NULL END AS id").each do
# ...
Select a specific column of your SQL query, execute the query and return an array containing this field.
User.query.pluck_col("id") # [1,2,3,4...]
Note: It returns an array of Clear::SQL::Any
. Therefore, you may want to use #pluck_col(str, Type)
to return
an array of Type
:
User.query.pluck_col("id", Int64)
The field argument is a SQL fragment; it's not escaped (beware SQL injection) and allow call to functions and aggregate methods:
# ...
User.query.pluck_col("CASE WHEN id % 2 = 0 THEN id ELSE NULL END AS id").each do
# ...