gizlang:odbc

Thin ODBC driver boundary. SQL semantics and planning belong to the data layer. Exact text/binary cells, bounded forward cursors, explicit transactions, no retries.

import * as Odbc from "gizlang:odbc";

Types

OdbcError

type OdbcError = { sqlstate: string; code: i64; message: string; }

An ODBC failure: its SQLSTATE, native code and message.

• sqlstate: string
• code: i64
• message: string

Column

type Column = { name: string; sqlType: i64; precision: i64; scale: i64; nullable: bool; }

A result column of an ODBC statement: its name, SQL type, precision, scale and whether it may be NULL.

• name: string
• sqlType: i64
• precision: i64
• scale: i64
• nullable: bool

Parameter

type Parameter = { sqlType: i64; precision: i64; scale: i64; binary: bool; value: Option<bytes>; }

A parameter of an ODBC statement: its SQL type, precision, scale, whether it is binary, and its value (none for NULL).

• sqlType: i64
• precision: i64
• scale: i64
• binary: bool
• value: _gizlang_sdk_core.Option<bytes>

Cell

type Cell = | { kind: "null"; } | { kind: "text"; value: string; } | { kind: "binary"; value: bytes; }

One cell of an ODBC result: NULL, text or binary.

• null
• text
• binary

Page

type Page = { rows: Vec<Vec<Cell>>; done: bool; }

A page of ODBC result rows, and whether it is the last.

• rows: Vec<Vec<gizlang_odbc.Cell>>
• done: bool

Capabilities

type Capabilities = { write: bool; transaction: bool; cancel: bool; }

What an ODBC data source supports: writes, transactions and cancelling a statement.

• write: bool
• transaction: bool
• cancel: bool

Connection

type Connection

A connection to an ODBC data source.

Opaque: create and use it through this module's functions.

Cursor

type Cursor

An open result of an ODBC statement, read page by page.

• connection: gizlang_odbc.Connection
• columns: Vec<gizlang_odbc.Column>
• cellBytes: i64

Functions

open

function open(sys: System, connectionString: string): Connection throws OdbcError

Driver-specific connection strings remain at this explicit external boundary.

Effects: fail, read, write, io.

Methods

Connection.prepare

function Connection.prepare(self: Connection, sql: string, params: Vec<Parameter>, cellBytes: i64): Cursor throws OdbcError

SQL prepared once with its parameter types PARAMS; each result cell is read into at most CELLBYTES bytes.

Effects: fail, read, write, io.

Connection.capabilities

function Connection.capabilities(self: Connection): Capabilities throws OdbcError

Driver-reported facts, not abilities inferred from the connection's spelling.

Effects: fail, read, io.

Cursor.poll

function Cursor.poll(self: Cursor, rows: i64, bytes: i64): Page throws OdbcError

Admission precedes SQLFetch; this page never retains more than rowBytes * rows.

Effects: fail, read, write, io.

Cursor.affected

function Cursor.affected(self: Cursor): i64 throws OdbcError

The number of rows that the statement changed (SQLRowCount).

Effects: fail, read, io.

Cursor.cancel

function Cursor.cancel(self: Cursor): bool throws OdbcError

Asks the driver to stop the statement that runs (SQLCancel).

Effects: fail, read, io.

Cursor.close

function Cursor.close(self: Cursor): bool

Frees the statement. It does nothing after the first call.

Effects: fail, read, write, io.

Connection.begin

function Connection.begin(self: Connection): bool throws OdbcError

Starts a transaction: autocommit is off until end.

Effects: fail, read, write, io.

Connection.end

function Connection.end(self: Connection, commit: bool): bool throws OdbcError

Ends the transaction: it commits when COMMIT, else rolls back; autocommit is on again.

Effects: fail, read, write, io.

Connection.close

function Connection.close(self: Connection): bool

Disconnects and frees the connection. It does nothing after the first call.

Effects: fail, read, write, io.