DBInterface.jl provides interface definitions to allow common database operations to be implemented consistently across various database packages.
To use DBInterface.jl, select an implementing database package, then utilize the consistent DBInterface.jl interface methods:
conn = DBInterface.connect(T, args...; kw...) # create a connection to a specific database T; required parameters are database-specific
stmt = DBInterface.prepare(conn, sql) # prepare a sql statement against the connection; returns a statement object
results = DBInterface.execute(stmt) # execute a prepared statement; returns an iterator of rows (property-accessible & indexable)
rowid = DBInterface.lastrowid(results) # get the last row id of an INSERT statement, as supported by the database
# example of using a query resultset
for row in results
@show propertynames(row) # see possible column names of row results
row.col1 # access the value of a column named `col1`
row[1] # access the first column in the row results
end
# results also implicitly satisfy the Tables.jl `Tables.rows` interface, so any compatible sink can ingest results
df = DataFrame(results)
CSV.write("results.csv", results)
results = DBInterface.execute(conn, sql) # convenience method if statement preparation/re-use isn't needed
stmt = DBInterface.prepare(conn, "INSERT INTO test_table VALUES(?, ?)") # prepare a statement with positional parameters
DBInterface.execute(stmt, [1, 3.14]) # execute the prepared INSERT statement, passing 1 and 3.14 as positional parameters
stmt = DBInterface.prepare(conn, "INSERT INTO test_table VALUES(:col1, :col2)") # prepare a statement with named parameters
DBInterface.execute(stmt, (col1=1, col2=3.14)) # execute the prepared INSERT statement, with 1 and 3.14 as named parameters
DBInterface.executemany(stmt, (col1=[1,2,3,4,5], col2=[3.14, 1.23, 2.34 3.45, 4.56])) # execute the prepared statement multiple times for each set of named parameters; each named parameter must be an indexable collection
results = DBInterface.executemultiple(conn, sql) # where sql is a query that returns multiple resultsets
# first iterate through resultsets
for result in results
# for each resultset, we can iterate through resultset rows
for row in result
@show propertynames(row)
row.col1
row[1]
end
end
DBInterface.close!(stmt) # close the prepared statement
DBInterface.close!(conn) # close connectionSee the documentation for expanded details on required interface methods.
