README.md

goracle

goracle is a package which is a database/sql/driver.Driver for connecting to Oracle DB, using Anthony Tuininga's excellent OCI wrapper, ODPI-C.

At least Go 1.9 is required!

Connect

In sql.Open("goracle", connString), you can provide the classic "user/passw@sid" as connString, or an URL like "oracle://user:passw@sid".

You can provide all possible options with ConnectionParams.

Rationale

With Go 1.9, driver-specific things are not needed, everything (I need) can be achieved with the standard database/sql library. Even calling stored procedures with OUT parameters, or sending/retrieving PL/SQL array types - just give a goracle.PlSQLArrays Option within the parameters of Exec!

The array size of the returned PL/SQL arrays can be set with goracle.ArraySize(2000)

• the default is 1024.

Connections are pooled by default (except AS SYSOPER or AS SYSDBA).

Speed

Correctness and simplicity is more important than speed, but the underlying ODPI-C library helps a lot with the lower levels, so the performance is not bad.

Queries are prefetched (256 rows by default, can be changed by adding a goracle.FetchRowCount(1000) argument to the call of Query), but you can speed up INSERT/UPDATE/DELETE statements by providing all the subsequent parameters at once, by putting each param's subsequent elements in a separate slice:

Instead of

db.Exec("INSERT INTO table (a, b) VALUES (:1, :2)", 1, "a")
db.Exec("INSERT INTO table (a, b) VALUES (:1, :2)", 2, "b")

do

db.Exec("INSERT INTO table (a, b) VALUES (:1, :2)", []int{1, 2}, []string{"a", "b"})

Logging

Goracle uses github.com/go-kit/kit/log's concept of a Log function. Either set goracle.Log to a logging function globally, or (better) set the logger in the Context of ExecContext or QueryContext:

db.QueryContext(goracle.ContextWithLog(ctx, logger.Log), qry)

Tracing

To set ClientIdentifier, ClientInfo, Module, Action and DbOp on the session, to be seen in the Database by the Admin, set goracle.TraceTag on the Context:

db.QueryContext(goracle.ContextWithTraceTag(goracle.TraceTag{
	Module: "processing",
	Action: "first",
}), qry)

Extras

To use the goracle-specific functions, you'll need a *goracle.conn. That's what goracle.DriverConn is for! See z_qrcn_test.go for using that to reach NewSubscription.

Caveats

sql.NullString

sql.NullString is not supported: Oracle DB does not differentiate between an empty string ("") and a NULL, so an

sql.NullString{String:"", Valid:true} == sql.NullString{String:"", Valid:false}

and this would be more confusing than not supporting sql.NullString at all.

Just use plain old string !

NUMBER

NUMBERs are transferred as goracle.Number (which is a string) to Go under the hood. This ensures that we don't lose any precision (Oracle's NUMBER has 38 decimal digits), and sql.Scan will hide this and Scan into your int64, float64 or string, as you wish.

For PLS_INTEGER and BINARY_INTEGER (PL/SQL data types) you can use int32.

Install

Just

go get gopkg.in/goracle.v2

Or if you prefer dep

dep ensure -add gopkg.in/goracle.v2

and you're ready to go!

Note that Windows may need some newer gcc (mingw-w64 with gcc 7.2.0).

Contribute

Just as with other Go projects, you don't want to change the import paths, but you can hack on the library in place, just set up different remotes:

cd $GOPATH.src/gopkg.in/goracle.v2
git remote add upstream https://github.com/go-goracle/goracle.git
git fetch upstream
git checkout -b master upstream/master

git checkout -f master
git pull upstream master
git remote add fork [email protected]:mygithubacc/goracle
git checkout -b newfeature upstream/master

Change, experiment as you wish, then

git commit -m 'my great changes' *.go
git push fork newfeature

and you're ready to send a GitHub Pull Request from github.com/mygithubacc/goracle, newfeature branch.

pre-commit

Add this to .git/hooks/pre-commit

#!/bin/sh
set -e

output="$(gofmt -l "$@")"

if [ -n "$output" ]; then
	echo >&2 "Go files must be formatted with gofmt. Please run:"
	for f in $output; do
		echo >&2 "  gofmt -w $PWD/$f"
	done
	exit 1
fi

gometalinter --vendor --disable-all \
  --enable=deadcode \
  --enable=ineffassign \
  --enable=gosimple \
  --enable=staticcheck \
  --enable=unused \
  --enable=vetshadow \
  --enable=maligned \
  --enable=vet \
  --enable=safesql \
  --enable=unconvert \
  --enable=gofmt \
  ./...

Third-party

• oracall generates a server for calling stored procedures.