ConnectionHandler {ResultModelManager}R Documentation

ConnectionHandler

Description

Class for handling DatabaseConnector:connection objects with consistent R6 interfaces for pooled and non-pooled connections. Allows a connection to cleanly be opened and closed and stored within class/object variables

Value

DatabaseConnector Connection instance close Connection

boolean TRUE if connection is valid queryDb

boolean TRUE if connection is valid executeSql

Public fields

connectionDetails

DatabaseConnector connectionDetails object

con

DatabaseConnector connection object

isActive

Is connection active or not#'

snakeCaseToCamelCase

(Optional) Boolean. return the results columns in camel case (default)

Methods

Public methods

Method new()

Usage
ConnectionHandler$new(
  connectionDetails,
  loadConnection = TRUE,
  snakeCaseToCamelCase = TRUE
)
Arguments
connectionDetails

DatabaseConnector::connectionDetails class

loadConnection

Boolean option to load connection right away

snakeCaseToCamelCase

(Optional) Boolean. return the results columns in camel case (default) get dbms

Method dbms()

Get the dbms type of the connection get table

Usage
ConnectionHandler$dbms()

Method tbl()

get a dplyr table object (i.e. lazy loaded)

Usage
ConnectionHandler$tbl(table, databaseSchema = NULL)
Arguments
table

table name

databaseSchema

databaseSchema to which table belongs Render Translate Sql.

Method renderTranslateSql()

Masked call to SqlRender

Usage
ConnectionHandler$renderTranslateSql(sql, ...)
Arguments
sql

Sql query string

...

Elipsis initConnection

Method initConnection()

Load connection Get Connection

Usage
ConnectionHandler$initConnection()

Method getConnection()

Returns connection for use with standard DatabaseConnector calls. Connects automatically if it isn't yet loaded

Usage
ConnectionHandler$getConnection()

Method closeConnection()

Closes connection (if active) close Connection

Usage
ConnectionHandler$closeConnection()

Method finalize()

Closes connection (if active) db Is Valid

Usage
ConnectionHandler$finalize()

Method dbIsValid()

Masks call to DBI::dbIsValid. Returns False if connection is NULL

Usage
ConnectionHandler$dbIsValid()

Method queryDb()

query database and return the resulting data.frame

If environment variable LIMIT_ROW_COUNT is set Returned rows are limited to this value (no default) Limit row count is intended for web applications that may cause a denial of service if they consume too many resources.

Usage
ConnectionHandler$queryDb(
  sql,
  snakeCaseToCamelCase = self$snakeCaseToCamelCase,
  overrideRowLimit = FALSE,
  ...
)
Arguments
sql

sql query string

snakeCaseToCamelCase

(Optional) Boolean. return the results columns in camel case (default)

overrideRowLimit

(Optional) Boolean. In some cases, where row limit is enforced on the system You may wish to ignore it.

...

Additional query parameters

Method executeSql()

execute set of database queries

Usage
ConnectionHandler$executeSql(sql, ...)
Arguments
sql

sql query string

...

Additional query parameters query Function

Method queryFunction()

queryFunction that can be overriden with subclasses (e.g. use different base function or intercept query) Does not translate or render sql.

Usage
ConnectionHandler$queryFunction(
  sql,
  snakeCaseToCamelCase = self$snakeCaseToCamelCase
)
Arguments
sql

sql query string

snakeCaseToCamelCase

(Optional) Boolean. return the results columns in camel case (default) execute Function

Method executeFunction()

exec query Function that can be overriden with subclasses (e.g. use different base function or intercept query) Does not translate or render sql.

Usage
ConnectionHandler$executeFunction(sql)
Arguments
sql

sql query string

Method clone()

The objects of this class are cloneable with this method.

Usage
ConnectionHandler$clone(deep = FALSE)
Arguments
deep

Whether to make a deep clone.

[Package ResultModelManager version 0.5.9 Index]