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Add index to caching table for search queries for increased speed

Source: R/tw_cache_indexing.R
tw_index_cache_item.Rd

Tested only with SQLite and MySql. May work with other drivers.

Usage

tw_index_cache_item(
  table_name = NULL,
  check_first = TRUE,
  type = "item",
  show_details = FALSE,
  language = tidywikidatar::tw_get_language(),
  cache = NULL,
  cache_connection = NULL,
  disconnect_db = TRUE
)

Arguments

table_name

Name of the table in the database. If given, it takes precedence over other parameters.

check_first

Logical, defaults to TRUE. If TRUE, then before executing anything on the database it checks if the given table has already been indexed. If it has, it does nothing and returns only an informative message.

type

Defaults to "item". Type of cache file to output. Values typically used by tidywikidatar include "item", "search_item", "search_property", and "qualifier".

show_details

Logical, defaults to FALSE. If FALSE, return the function adds the index to the database, but does not return anything. If TRUE, returns a data frame with more details about the index.

language

Defaults to language set with tw_set_language(); "en" if not set. Used to limit the data to be cached. Use "all_available" to keep all data. For available values, see https://www.wikidata.org/wiki/Help:Wikimedia_language_codes/lists/all

cache

Defaults to NULL. If given, it should be given either TRUE or FALSE. Typically set with tw_enable_cache() or tw_disable_cache().

cache_connection

Defaults to NULL. If NULL, and caching is enabled, tidywikidatar will use a local sqlite database. A custom connection to other databases can be given (see vignette caching for details).

disconnect_db

Defaults to TRUE. If FALSE, leaves the connection to cache open.

Value

If show_details is set to FALSE, nothing, used only for its side effects (add index to caching table). If TRUE, a data frame, same as the output of tw_check_cache_index(show_details = TRUE).

Details

To ensure smooth functioning, the search column in the cache table is transformed into a column of type varchar and length 255.

Examples

if (interactive()) {
  tw_enable_cache()
  tw_set_cache_folder(path = fs::path(
    fs::path_home_r(),
    "R",
    "tw_data"
  ))

  tw_index_cache_search()
}