R: Relational Query Generator for Data Manipulation at Scale

# Relational Query Generator for Data Manipulation at Scale

## Documentation for package ‘rquery’ version 1.4.99

- DESCRIPTION file.
- User guides, package vignettes and other documentation.

## Help Pages

A B C D E F G I K L M N O P Q R S T U W

rquery-package | '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_join_plan | 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_node | 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 --

unionall | Make an unionall node (not a relational operation).

## -- W --

wrap | Wrap a data frame for later execution.