Relational Query Generator for Data Manipulation at Scale

Documentation for package ‘rquery’ version 1.4.99

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'rquery': Relational Query Generator for Data Manipulation

-- A --

actualize_join_plan	Execute an ordered sequence of left joins.
affine_transform	Implement an affine transformaton
aggregate_nse	project data by grouping, and adding aggregate columns.
aggregate_se	project data by grouping, and adding aggregate columns.
apply_right.relop	Execute pipeline treating pipe_left_arg as local data to be copied into database.
apply_right_S4-method	Apply pipeline to a database.
apply_right_S4-method	S4 dispatch method for apply_right.
apply_right_S4-method	S4 dispatch method for apply_right.
arrow	Data arrow
assign_slice	Assign a value to a slice of data (set of rows meeting a condition, and specified set of columns).

-- B --

Build a join plan.

-- C --

columns_used	Return columns used
column_names	Return column names
commencify	Hyderdrive (science fiction show) synonym for 'execute'
complete_design	Complete an experimental design.
convert_yaml_to_pipeline	Convert a series of simple objects (from YAML deserializaton) to an rquery pipeline.
count_null_cols	Count NULLs per row for given column set.

-- D --

dbi_table	Construct a table description from a database source.
db_td	Construct a table description from a database source.
describe_tables	Build a nice description of a table.
drop_columns	Make a drop columns node (not a relational operation).

-- E --

ex	Execute a wrapped execution pipeline.
execute	Execute an operator tree, bringing back the result to memory.
expand_grid	Cross product vectors in database.
extend	Extend data by adding more columns.
extend_nse	Extend data by adding more columns.
extend_se	Extend data by adding more columns.

-- F --

Format a single node for printing.

-- G --

getDBOption	Get a database connection option.
graph_join_plan	Build a draw-able specification of the join diagram

-- I --

if_else_block	Build a sequence of statements simulating an if/else block-'if(){}else{}'.
if_else_op	Build a 'relop' node simulating a per-row block-'if(){}else{}'.
inspect_join_plan	check that a join plan is consistent with table descriptions.

-- K --

key_inspector_all_cols	Return all columns as guess of preferred primary keys.
key_inspector_postgresql	Return all primary key columns as guess at preferred primary keys for a PostgreSQL handle.
key_inspector_sqlite	Return all primary key columns as guess at preferred primary keys for a SQLite handle.

-- L --

local_td	Construct a table description of a local data.frame.
lookup_by_column	Use one column to pick values from other columns.

-- M --

make_assignments	Make a list of assignments, applying many functions to many columns.
map_column_values	Remap values in a set of columns.
mark_null_cols	Indicate NULLs per row for given column set.
materialize	Materialize an optree as a table.
materialize_node	Create a materialize node.
mk_td	Make a table description directly.

-- N --

natural_join	Make a natural_join node.
non_sql_node	Wrap a non-SQL node.
normalize_cols	Build an optree pipeline that normalizes a set of columns so each column sums to one in each partition.
null_replace	Create a null_replace node.

-- O --

op_diagram	Build a diagram of a optree pipeline.
orderby	Make an orderby node (not a relational operation).
order_expr	Make a order_expr node.
order_expr_nse	Make a order_expr node.
order_expr_se	Make a order_expr node.
order_rows	Make an orderby node (not a relational operation).

-- P --

pick_top_k	Build an optree pipeline that selects up to the top k rows from each group in the given order.
pre_sql_sub_expr	pre_sql_sub_expr
project	project data by grouping, and adding aggregate columns.
project_nse	project data by grouping, and adding aggregate columns.
project_se	project data by grouping, and adding aggregate columns.

-- Q --

quantile_cols	Compute quantiles of specified columns (without interpolation, needs a database with window functions).
quantile_node	Compute quantiles over non-NULL values (without interpolation, needs a database with window functions).
quote_identifier	Quote an identifier.
quote_literal	Quote a value
quote_string	Quote a string
quote_table_name	Quote a table name.

-- R --

rename_columns	Make a rename columns node (copies columns not renamed).
rlook	Quick look at remote data
row_counts	Build an optree pipeline counts rows.
rquery	'rquery': Relational Query Generator for Data Manipulation
rquery_apply_to_data_frame	Execute optree in an environment where d is the only data.
rquery_db_info	Build a db information stand-in
rquery_default_db_info	An example 'rquery_db_info' object useful for formatting 'SQL' without a database connection.
rq_colnames	List table column names.
rq_coltypes	Get column types by example values as a data.frame.
rq_connection_advice	Get advice for a DB connection (beyond tests).
rq_connection_name	Build a canonical name for a db connection class.
rq_connection_tests	Try and test database for some option settings.
rq_copy_to	Copy local R table to remote data handle.
rq_execute	Execute a query, typically an update that is not supposed to return results.
rq_get_query	Execute a get query, typically a non-update that is supposed to return results.
rq_head	Get head of db table
rq_nrow	Count rows and return as numeric
rq_remove_table	Remove table
rq_table_exists	Check if a table exists.
rstr	Quick look at remote data
rsummary	Compute usable summary of columns of remote table.
rsummary_node	Create an rsumary relop operator node.

-- S --

select_columns	Make a select columns node (not a relational operation).
select_rows	Make a select rows node.
select_rows_nse	Make a select rows node.
select_rows_se	Make a select rows node.
setDBOpt	Set a database connection option.
setDBOption	Set a database connection option.
set_indicator	Make a set indicator node.
sql_expr_set	Build a query that applies a SQL expression to a set of columns.
sql_node	Make a general SQL node.

-- T --

tables_used	Return vector of table names used.
table_source	Make a table description directly.
theta_join	Make a theta_join node.
theta_join_nse	Make a theta_join node.
theta_join_se	Make a theta_join node.
topo_sort_tables	Topologically sort join plan so values are available before uses.
to_sql	Return SQL implementation of operation tree.
to_transport_representation	Convert an rquery op diagram to a simple representation, appropriate for conversion to YAML.

-- U --

Make an unionall node (not a relational operation).

-- W --

wrap	Wrap a data frame for later execution.