Oracle

Oracle Database support with PL/SQL dialect parsing, bind variable syntax, and type mappings across all 10 languages.

Overview

Oracle Database is an enterprise relational database with its own SQL dialect and type system. Scythe supports Oracle-specific types like NUMBER, VARCHAR2, and DATE (which includes time), and uses :N bind variable syntax for parameter placeholders.

Engine alias

scythe.toml

[[sql]]
engine = "oracle"

Supported backends

Backend	Language	Driver
rust-sibyl	Rust	sibyl
python-oracledb	Python	oracledb (python-oracledb)
typescript-oracledb	TypeScript	oracledb (node-oracledb)
go-godror	Go	godror
java-jdbc	Java	JDBC (Oracle JDBC / ojdbc)
kotlin-jdbc	Kotlin	JDBC (Oracle JDBC / ojdbc)
csharp-oracle	C#	ODP.NET (Oracle.ManagedDataAccess)
ruby-oci8	Ruby	ruby-oci8
elixir-jamdb	Elixir	jamdb_oracle

java-r2dbc, kotlin-r2dbc, and php-pdo do not support Oracle – their supported_engines lists do not include oracle.

Configuration

scythe.toml

[[sql]]
name = "main"
engine = "oracle"
schema = ["schema.sql"]
queries = ["queries/"]

[[sql.gen]]
backend = "java-jdbc"
output = "src/generated"

Type mapping table

Oracle Type	Neutral Type	Notes
INTEGER / INT	int64	Alias for NUMBER(38,0)
NUMBER(p, s) where s > 0	decimal	Explicit non-zero scale
NUMBER(p) / NUMBER(p, 0)	int64	Explicit precision, zero (or implied zero) scale
NUMBER (table column, no precision or scale)	int64	Pragmatic default. Real schemas overwhelmingly use bare NUMBER as an integer/boolean-flag column (e.g. NUMBER(1)); a table column’s bare NUMBER is indistinguishable from NUMBER(p) by the time it reaches type resolution
NUMBER (in CAST(... AS NUMBER) or parameter/return type inference, not a column)	decimal	Oracle’s true “floating” type outside DDL: no precision or scale means it can hold fractional values
BINARY_FLOAT	float32
BINARY_DOUBLE	float64
VARCHAR2 / NVARCHAR2 / CHAR / NCHAR	string
CLOB / NCLOB	string
RAW / BLOB	bytes
DATE	datetime	Oracle DATE includes time
TIMESTAMP	datetime
TIMESTAMP WITH TIME ZONE	datetime_tz
TIMESTAMP WITH LOCAL TIME ZONE	datetime_tz
INTERVAL YEAR TO MONTH	interval
INTERVAL DAY TO SECOND	interval
BOOLEAN	bool	Oracle 23c+

XMLTYPE has no type mapping (only the generic XML spelling does). A column declared XMLTYPE fails code generation.

Placeholder syntax

Oracle uses :N bind variable placeholders:

INSERT INTO users (name, email) VALUES (:1, :2);

Scythe translates $N in your SQL to :N for Oracle backends:

-- Written as:
SELECT id, name FROM users WHERE id = $1;

-- Translated to:
SELECT id, name FROM users WHERE id = :1;

Docker setup

CI runs Oracle integration tests against gvenzl/oracle-xe:21-slim:

docker run -e ORACLE_PASSWORD=oracle -p 1521:1521 --name oracle \
  gvenzl/oracle-xe:21-slim

Notes

• Oracle DATE – Unlike most databases, Oracle’s DATE type includes time (hour, minute, second). It maps to datetime, not date.
• NUMBER type – Oracle uses NUMBER(precision, scale) for all numeric types. See the type mapping table above for the full split between column definitions and direct AST resolution (CAST, parameters).
• DUAL table – Oracle requires SELECT ... FROM DUAL for expressions without a table. Scythe handles this in query parsing.
• No BOOLEAN before 23c – Oracle versions before 23c have no native BOOLEAN type. Use NUMBER(1) with a type override if targeting older versions.
• RETURNING INTO – Oracle uses RETURNING ... INTO :var syntax. Scythe translates RETURNING clauses appropriately.
• Empty string is NULL – Oracle stores a zero-length string as NULL: '' and N'' literals evaluate to NULL, not an empty value. This affects nullability inference – COALESCE(email, '') is non-nullable everywhere else (the literal fallback proves it), but stays nullable on Oracle because the fallback itself is NULL there. See Type Inference and the live conformance fixture testing_data/nullability_live/coalesce_non_null/live_coalesce_with_empty_string_default_is_null_on_oracle.json.