rocker-R6-class function

'rocker' Database Interface R6 Class

R6 class interface for handling database connections using DBI package as backend. The class allows handling of connections to e.g. PostgreSQL, MariaDB and SQLite.

Format

R6Class

Examples

# New database handling object
db <- rocker::newDB()
# Setup SQLite database
db$setupSQLite()
# Open connection
db$connect()
# Write table
db$writeTable("mtcars", mtcars)
# Get query
output <- db$getQuery("SELECT * FROM mtcars;")
# Close connection
db$disconnect()
# Reset database handling object
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$setupDriver`
## ------------------------------------------------

db <- rocker::newDB()
db$setupDriver(
  drv = RSQLite::SQLite(),
  dbname = ":memory:"
)
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$setupPostgreSQL`
## ------------------------------------------------

db <- rocker::newDB()
db$setupPostgreSQL(
  host = "127.0.0.1", port = "5432", dbname = "mydb",
  user = "postgres", password = "password"
)
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$setupMariaDB`
## ------------------------------------------------

db <- rocker::newDB()
db$setupMariaDB(
  host = "127.0.0.1", port = "3306", dbname = "mydb",
  user = "root", password = "password"
)
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$setupSQLite`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite(
  dbname = ":memory:"
)
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$unloadDriver`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$canConnect`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$canConnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$connect`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$disconnect`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$sendQuery`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getQuery`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
output <- db$getQuery("SELECT * FROM mtcars;")
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$sendStatement`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$execute`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$execute("DELETE FROM mtcars WHERE gear = 3;")
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$fetch`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$hasCompleted`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch(5)
db$hasCompleted()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getRowsAffected`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$getRowsAffected()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getRowCount`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$getRowCount()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$columnInfo`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$columnInfo()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getStatement`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$getStatement()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$clearResult`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$begin`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$begin()
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$commit()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$commit`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$begin()
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$commit()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$rollback`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$begin()
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$rollback()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getInfoDrv`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$getInfoDrv()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getInfoCon`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$getInfoCon()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$getInfoRes`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$getInfoRes()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$isValidDrv`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$isValidDrv()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$isValidCon`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$isValidCon()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$isValidRes`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$isValidRes()
db$clearResult()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$validateCon`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$validateCon()
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$createTable`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$createTable("mtcars", mtcars)
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$appendTable`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$createTable("mtcars", mtcars)
db$appendTable("mtcars", mtcars)
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$writeTable`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$readTable`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
output <- db$readTable("mtcars")
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$removeTable`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$removeTable("mtcars")
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$existsTable`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$existsTable("mtcars")
db$disconnect()
db$unloadDriver()

## ------------------------------------------------
## Method `rocker$listFields`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$listFields("mtcars")
db$disconnect()

## ------------------------------------------------
## Method `rocker$listObjects`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$listObjects()
db$disconnect()

## ------------------------------------------------
## Method `rocker$listTables`
## ------------------------------------------------

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$listTables()
db$disconnect()

See Also

Other rocker: newDB(), rocker-README, rocker-S3-functions, rocker-package

Active bindings

• .drv: Read only DBI::DBIDriver-class object or NULL. It is recommended not to use this object! For advanced user, object can be used for direct execution of functions from DBI package.

• .con: Read only DBI::DBIConnection-class object or NULL. It is recommended not to use this object! For advanced user, object can be used for direct execution of functions from DBI package.

• .res: Read only DBI::DBIResult-class object or NULL. It is recommended not to use this object! For advanced user, object can be used for direct execution of functions from DBI package.

• transaction: Read only TRUE or FALSE. Information on pending transaction.

• info: Read only driver package and connection parameter information list.

• verbose: TRUE or FALSE. Switch text output on / off.

• id: Optional object ID/name

• validateQuery: SQL statement used in validateCon

Methods

Public methods

• list("rocker$new()")

• list("rocker$print()")

• list("rocker$setupDriver()")

• list("rocker$setupPostgreSQL()")

• list("rocker$setupMariaDB()")

• list("rocker$setupSQLite()")

• list("rocker$unloadDriver()")

• list("rocker$canConnect()")

• list("rocker$connect()")

• list("rocker$disconnect()")

• list("rocker$sendQuery()")

• list("rocker$getQuery()")

• list("rocker$sendStatement()")

• list("rocker$execute()")

• list("rocker$fetch()")

• list("rocker$hasCompleted()")

• list("rocker$getRowsAffected()")

• list("rocker$getRowCount()")

• list("rocker$columnInfo()")

• list("rocker$getStatement()")

• list("rocker$clearResult()")

• list("rocker$begin()")

• list("rocker$commit()")

• list("rocker$rollback()")

• list("rocker$getInfoDrv()")

• list("rocker$getInfoCon()")

• list("rocker$getInfoRes()")

• list("rocker$isValidDrv()")

• list("rocker$isValidCon()")

• list("rocker$isValidRes()")

• list("rocker$validateCon()")

• list("rocker$createTable()")

• list("rocker$appendTable()")

• list("rocker$writeTable()")

• list("rocker$readTable()")

• list("rocker$removeTable()")

• list("rocker$existsTable()")

• list("rocker$listFields()")

• list("rocker$listObjects()")

• list("rocker$listTables()")

Method new()

Generate new instance of class.

Usage

rocker$new(verbose = TRUE, id = NULL, ...)

Arguments

• verbose: TRUE or FALSE. Switch text output on / off.

• id: Optional object ID/name

• ...: Not used yet

Returns

New instance of class

Method print()

Print object information.

Usage

rocker$print()

Returns

Invisible self

Method setupDriver()

Setup database driver and define connection parameters.

Usage

rocker$setupDriver(drv, protect = c("password", "user"), ...)

Arguments

• drv: Driver object from suitable package e.g. RPostgres::Postgres(), RMariaDB::MariaDB() and RSQLite::SQLite()

• protect: Parameters to be hidden

• ...: Suitable parameters passed to DBI::dbConnect() e.g. host, port, dbname, user and password

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupDriver(
  drv = RSQLite::SQLite(),
  dbname = ":memory:"
)
db$unloadDriver()

Method setupPostgreSQL()

Setup database driver and define connection parameters for PostgreSQL using RPostgres package. Wrapper for setupDriver() function.

Usage

rocker$setupPostgreSQL(
  host = "127.0.0.1",
  port = "5432",
  dbname = "mydb",
  user = "postgres",
  password = "password",
  protect = c("password", "user"),
  ...
)

Arguments

• host: Host name or IP number

• port: Port number

• dbname: Database name

• user: User name

• password: Password

• protect: Parameters to be hidden

• ...: Optional, additional suitable parameters passed to DBI::dbConnect()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupPostgreSQL(
  host = "127.0.0.1", port = "5432", dbname = "mydb",
  user = "postgres", password = "password"
)
db$unloadDriver()

Method setupMariaDB()

Setup database driver and define connection parameters for MariaDB using RMariaDB package. Wrapper for setupDriver() function.

Usage

rocker$setupMariaDB(
  host = "127.0.0.1",
  port = "3306",
  dbname = "mydb",
  user = "root",
  password = "password",
  protect = c("password", "user"),
  ...
)

Arguments

• host: Host name or IP number

• port: Port number

• dbname: Database name

• user: User name

• password: Password

• protect: Parameters to be hidden

• ...: Optional, additional suitable parameters passed to DBI::dbConnect()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupMariaDB(
  host = "127.0.0.1", port = "3306", dbname = "mydb",
  user = "root", password = "password"
)
db$unloadDriver()

Method setupSQLite()

Setup database driver and define connection parameters for SQLite using RSQLite package. Wrapper for setupDriver() function.

Usage

rocker$setupSQLite(dbname = ":memory:", protect = c("password", "user"), ...)

Arguments

• dbname: Database name

• protect: Parameters to be hidden

• ...: Optional, additional suitable parameters passed to DBI::dbConnect()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite(
  dbname = ":memory:"
)
db$unloadDriver()

Method unloadDriver()

Reset database driver and connection parameters.

Usage

rocker$unloadDriver(...)

Arguments

• ...: Optional, suitable parameters passed to DBI::dbUnloadDriver()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$unloadDriver()

Method canConnect()

Test connection parameters.

Usage

rocker$canConnect(...)

Arguments

• ...: Optional, suitable parameters passed to DBI::dbCanConnect()

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$canConnect()
db$unloadDriver()

Method connect()

Establish database connection using stored parameters.

Usage

rocker$connect(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbConnect()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$disconnect()
db$unloadDriver()

Method disconnect()

Disconnect database.

Usage

rocker$disconnect(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbDisconnect()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$disconnect()
db$unloadDriver()

Method sendQuery()

Send SQL query to database.

Usage

rocker$sendQuery(statement, ...)

Arguments

• statement: SQL query (SELECT)

• ...: Optional, additional suitable parameters passed to DBI::dbSendQuery()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method getQuery()

Retrieve SQL query from database. Combination of functions sendQuery(), fetch() and clearResult(). If required, database is automatically connected and disconnected.

Usage

rocker$getQuery(statement, n = -1, ...)

Arguments

• statement: SQL query (SELECT)

• n: Number of record to be fetched at once. All records will be fetched.

• ...: Optional, additional suitable parameters passed to DBI::dbSendQuery()

Returns

Records

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
output <- db$getQuery("SELECT * FROM mtcars;")
db$disconnect()
db$unloadDriver()

Method sendStatement()

Send SQL statement to database.

Usage

rocker$sendStatement(statement, ...)

Arguments

• statement: SQL statement (UPDATE, DELETE, INSERT INTO, ...)

• ...: Optional, additional suitable parameters passed to DBI::dbSendStatement()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$disconnect()
db$unloadDriver()

Method execute()

Execute SQL statement in database. Combination of functions execute and clearResult. If required, database is automatically connected and disconnected.

Usage

rocker$execute(statement, ...)

Arguments

• statement: SQL statement (UPDATE, DELETE, INSERT INTO, ...)

• ...: Optional, additional suitable parameters passed to DBI::dbSendStatement()

Returns

Number of affected rows

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$execute("DELETE FROM mtcars WHERE gear = 3;")
db$disconnect()
db$unloadDriver()

Method fetch()

Fetch SQL query result from database.

Usage

rocker$fetch(n = -1, ...)

Arguments

• n: Number of record to be fetched

• ...: Optional, additional suitable parameters passed to DBI::dbFetch()

Returns

Records

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method hasCompleted()

Information whether all records were retrieved.

Usage

rocker$hasCompleted(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbHasCompleted()

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch(5)
db$hasCompleted()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method getRowsAffected()

Information on number of affected rows.

Usage

rocker$getRowsAffected(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbGetRowsAffected()

Returns

Number of affected rows

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$getRowsAffected()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method getRowCount()

Information on number of retrieved rows.

Usage

rocker$getRowCount(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbGetRowCount()

Returns

Number of retrieved rows

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$getRowCount()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method columnInfo()

Information on query result columns.

Usage

rocker$columnInfo(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbColumnInfo()

Returns

Information table

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$columnInfo()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method getStatement()

Information on sent statement.

Usage

rocker$getStatement(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbGetStatement()

Returns

Statement text

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$getStatement()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method clearResult()

Clear query or statement result.

Usage

rocker$clearResult(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbClearResult()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
output <- db$fetch()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method begin()

Begin transaction.

Usage

rocker$begin(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbBegin()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$begin()
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$commit()
db$disconnect()
db$unloadDriver()

Method commit()

Commit transaction.

Usage

rocker$commit(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbCommit()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$begin()
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$commit()
db$disconnect()
db$unloadDriver()

Method rollback()

Rollback transaction.

Usage

rocker$rollback(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbRollback()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$begin()
db$sendStatement("DELETE FROM mtcars WHERE gear = 3;")
db$clearResult()
db$rollback()
db$disconnect()
db$unloadDriver()

Method getInfoDrv()

Information on driver object.

Usage

rocker$getInfoDrv(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbGetInfo()

Returns

Information list

Examples

db <- rocker::newDB()
db$setupSQLite()
db$getInfoDrv()
db$unloadDriver()

Method getInfoCon()

Information on connection object.

Usage

rocker$getInfoCon(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbGetInfo()

Returns

Information list

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$getInfoCon()
db$disconnect()
db$unloadDriver()

Method getInfoRes()

Information on result object.

Usage

rocker$getInfoRes(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbGetInfo()

Returns

Information list

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$getInfoRes()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method isValidDrv()

Check driver object.

Usage

rocker$isValidDrv(onLostNull = FALSE, ...)

Arguments

• onLostNull: TRUE or FALSE. If driver lost, set .drv to NULL

• ...: Optional, additional suitable parameters passed to DBI::dbIsValid()

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$isValidDrv()
db$unloadDriver()

Method isValidCon()

Check connection object.

Usage

rocker$isValidCon(onLostNull = FALSE, ...)

Arguments

• onLostNull: TRUE or FALSE. If connection lost, set .con to NULL

• ...: Optional, additional suitable parameters passed to DBI::dbIsValid()

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$isValidCon()
db$disconnect()
db$unloadDriver()

Method isValidRes()

Check result object.

Usage

rocker$isValidRes(onLostNull = FALSE, ...)

Arguments

• onLostNull: TRUE or FALSE. If result lost, set .res to NULL

• ...: Optional, additional suitable parameters passed to DBI::dbIsValid()

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$sendQuery("SELECT * FROM mtcars;")
db$isValidRes()
db$clearResult()
db$disconnect()
db$unloadDriver()

Method validateCon()

Check if an earlier opened connection is still open.

Usage

rocker$validateCon(statement = NULL, onLostNull = FALSE, ...)

Arguments

• statement: Optional SQL statement. If not set default validateQuery will be used.

• onLostNull: TRUE or FALSE. If connection lost, set .con to NULL

• ...: Not used yet

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$validateCon()
db$disconnect()
db$unloadDriver()

Method createTable()

Create empty formatted table.

Usage

rocker$createTable(name, fields, ...)

Arguments

• name: Table name

• fields: Template data.frame

• ...: Optional, additional suitable parameters passed to DBI::dbCreateTable()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$createTable("mtcars", mtcars)
db$disconnect()
db$unloadDriver()

Method appendTable()

Append data to table.

Usage

rocker$appendTable(name, value, ...)

Arguments

• name: Table name

• value: Values data.frame

• ...: Optional, additional suitable parameters passed to DBI::dbAppendTable()

Returns

Number of appended rows invisibly

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$createTable("mtcars", mtcars)
db$appendTable("mtcars", mtcars)
db$disconnect()
db$unloadDriver()

Method writeTable()

Write data to table.

Usage

rocker$writeTable(name, value, ...)

Arguments

• name: Table name

• value: Values data.frame

• ...: Optional, additional suitable parameters passed to DBI::dbWriteTable()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$disconnect()
db$unloadDriver()

Method readTable()

Read table.

Usage

rocker$readTable(name, ...)

Arguments

• name: Table name

• ...: Optional, additional suitable parameters passed to DBI::dbReadTable()

Returns

Table

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
output <- db$readTable("mtcars")
db$disconnect()
db$unloadDriver()

Method removeTable()

Remove table.

Usage

rocker$removeTable(name, ...)

Arguments

• name: Table name

• ...: Optional, additional suitable parameters passed to DBI::dbRemoveTable()

Returns

Invisible self

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$removeTable("mtcars")
db$disconnect()
db$unloadDriver()

Method existsTable()

Check if table exists.

Usage

rocker$existsTable(name, ...)

Arguments

• name: Table name

• ...: Optional, additional suitable parameters passed to DBI::dbExistsTable()

Returns

TRUE or FALSE

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$existsTable("mtcars")
db$disconnect()
db$unloadDriver()

Method listFields()

List table column names.

Usage

rocker$listFields(name, ...)

Arguments

• name: Table name

• ...: Optional, additional suitable parameters passed to DBI::dbListFields()

Returns

Column names

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$listFields("mtcars")
db$disconnect()

Method listObjects()

List database objects.

Usage

rocker$listObjects(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbListObjects()

Returns

List of objects

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$listObjects()
db$disconnect()

Method listTables()

List database tables.

Usage

rocker$listTables(...)

Arguments

• ...: Optional, additional suitable parameters passed to DBI::dbListTables()

Returns

List of objects

Examples

db <- rocker::newDB()
db$setupSQLite()
db$connect()
db$writeTable("mtcars", mtcars)
db$listTables()
db$disconnect()