create_extended_main_joint_tables: Create Extended Main Joint Tables

In N1h1l1sT/dbautojoinr: Automatic Joining of SQL Tables

Description

Get a list of all the Main tables in the database joined with all their relationships, Renaming Columns in certain tables according to "db_ColumnsOldNamesToNewNames" and then joining the renamed columns according to the relationship that exists on "db_forced_rel" for original column name (IF it exists). This way, if, for instance, both lstTables[[DIM_Employee]] and lstTables[[FACT_Work]] reference lstTables[[DIM_Site]], then Site can be renamed to MainSite and Extended_Join on lstTables[[DIM_Employee]] as this table refers to the main/base Site of the Employee, whilst lstTables[[FACT_Work]] refers to the Site the employee worked on at that point of time (row).

Usage

create_extended_main_joint_tables(
  db_fields,
  db_forced_rel,
  db_ColumnsOldNamesToNewNames,
  con = db$con,
  Verbose = TRUE,
  get_sql_query = TRUE
)

Arguments

db_fields	A DF with columns: "Include, KeyType, Table, Column, Type, RelationshipWithTable, RelationshipWithColumn, Transformation, Comment" about the User Selected fields and Relationships
db_forced_rel	A Named String Vector. The vector names MUST point to the main table to be used for the 1-Joint-Table as its LHS
db_ColumnsOldNamesToNewNames	A named List. Names correspond to the Table names, and the vectors inside will be used to renamed SQL Columns starting with db_ColumnsOldNamesToNewNames[i][j] to db_ColumnsOldNamesToNewNames[i][j+1] with j going from 1 to length of db_ColumnsOldNamesToNewNames[i] by 2
con	is a dbConnect DBI connection object to a SQL Database
Verbose	A Boolean. Verbose = TRUE will output the consecutive joins as they happen
get_sql_query	A Boolean. get_sql_query = TRUE will create/edit the db$sql_main_joint_tables that output the SQL Code for the tables

Examples

extended_main_joint_tables <-
  create_extended_main_joint_tables(db_fields,
                                    db_forced_rel = c(Hours_SiteID = "Site_SiteID", Hours_EmployeeID = "Employee_ID"),
                                    db_ColumnsOldNamesToNewNames =
                                      list(
                                           DIM_Employee = c(
                                                            c("Site_", "MainSite_")
                                                           )
                                           )
                                    )

print(extended_main_joint_tables)

N1h1l1sT/dbautojoinr documentation built on Jan. 24, 2021, 10:15 a.m.