MS SQL Server Driver

The MSSQL driver supports Queen's core flow using SQL Server application locks.

Packages

import (
    "database/sql"

    "github.com/yaop-labs/queen"
    "github.com/yaop-labs/queen/drivers/mssql"
    _ "github.com/microsoft/go-mssqldb"
)

db, err := sql.Open("sqlserver", os.Getenv("MSSQL_DSN"))
if err != nil {
    return err
}

q := queen.New(mssql.New(db))

How it works

Area	Implementation
Migration table	Created with IF OBJECT_ID(..., 'U') IS NULL.
Identifier quoting	Brackets.
Placeholders	@p1, @p2, ...
Locking	sp_getapplock with LockOwner = 'Session' on a pinned *sql.Conn.
Unlock	sp_releaseapplock on the same connection.
Lock name	queen_lock_ plus migration table name.
Execution	database/sql transaction through the shared base driver.
Atomic record	No. Migration body commits before Record.

Guarantees

• Lock connection lifecycle is mutex-guarded.
• Nested lock attempts on the same driver fail deterministically.
• Table names used in OBJECT_ID(N'...') string literals escape single quotes.

Limitations

• Migration metadata is not atomic with the migration body.
• SQL Server DDL transaction behavior depends on the statement and database settings.
• This path is supported but less heavily exercised than PostgreSQL.

DSN

sqlserver://user:pass@localhost:1433?database=myapp