read_sql: read_sql

In skysyzygy/tessilake: Data lake for Tessitura

read_sql

Description

Execute a database query and cache it locally as a Feather file and remotely as a Parquet file. Cache storage locations are managed by tessilake.depths options. Database connection defined by an ODBC profile with the name set by the tessilake.tessitura option.

Usage

read_sql(
  query,
  name = digest::sha1(query),
  select = NULL,
  primary_keys = NULL,
  date_column = NULL,
  freshness = as.difftime(7, units = "days"),
  incremental = TRUE,
  ...
)

read_sql_table(
  table_name,
  schema = "dbo",
  select = NULL,
  primary_keys = NULL,
  date_column = NULL,
  freshness = as.difftime(7, units = "days"),
  incremental = TRUE,
  ...
)

Arguments

query	character query to run on the database.
name	name of the query, defaults to the SHA1 hash of the query.
select	vector of strings indicating columns to select from database
primary_keys	character vector, primary keys of the table. read_sql_table will attempt to identify the primary keys using SQL metadata.
date_column	character, date column of the table showing the last date the row was updated. Defaults to "last_update_dt" if it exists in the table.
freshness	the returned data will be at least this fresh
incremental	whether or not to load data incrementally, default is TRUE
...	Arguments passed on to write_cache
table_name	character, table name without schema.
schema	character, database schema. Default is dbo

Value

an Apache arrow::Table

an Apache arrow::Table.

Functions

• read_sql_table(): Reads a table or view from a SQL database and caches it locally using read_sql.

Examples

## Not run: 
read_sql("select * from T_CUSTOMER", "t_customer",
  primary_keys = "customer_no",
  date_column = "last_update_dt"
)

## End(Not run)
## Not run: 
read_sql_table("T_CUSTOMER")

## End(Not run)

skysyzygy/tessilake documentation built on June 14, 2025, 6:50 p.m.