Read-only query over the local Zotero database

Opens the local zotero.sqlite database in read-only mode. Local records can lag the Web API until the desktop client synchronizes, and WAL mode can make recent local changes temporarily unavailable to another reader.

Usage

zotLocalQuery(
  sql,
  params = list(),
  path = file.path(Sys.getenv("HOME"), "Zotero", "zotero.sqlite")
)

Arguments

sql

One read-only SQL statement.

params

Positional query parameters.

path

Database file (default: the standard Zotero location).

Value

Query result as a data.table.

Details

The database connection is opened with SQLite's read-only flag, without issuing any PRAGMA, and closed when the query finishes. zotLocalQuery() does not copy or modify the desktop database. The caller remains responsible for supplying a read-only SQL statement. The default path is ~/Zotero/zotero.sqlite; pass path explicitly for a portable installation or a custom Zotero data directory.

While Zotero is writing, it locks the database. A read waits for the write to finish for up to LOCALWAIT, a package constant of 10000 milliseconds (10 s). If the database is still locked after that wait, the query fails with a zotLocalError naming the wait and the original SQLite error; any other SQLite error propagates unchanged.

See also

zotLocalItems() and zotRequest().

Examples

Path <- tempfile(fileext = ".sqlite")
Connection <- DBI::dbConnect(RSQLite::SQLite(), Path)
DBI::dbWriteTable(Connection, "items", data.frame(key = c("A", "B")))
DBI::dbDisconnect(Connection)
zotLocalQuery("SELECT key FROM items ORDER BY key", path = Path)
#>       key
#>    <char>
#> 1:      A
#> 2:      B
unlink(Path)