Cheat sheet

The whole surface on one screen. Each row links to the guide that explains it. For exact signatures, see pkg.go.dev/liteorm.org.

Open a backend

db, err := sqlite.Open("app.db")                 // also OpenEncrypted(path, key), OpenConfig(cfg)
db, err := postgres.Open(ctx, dsn)               // native pgx
db, err := mysql.Open(ctx, dsn)
db, err := mssql.Open(ctx, dsn)
defer db.Close()

*liteorm.DB and a transaction (db.Begin(ctx)) are both a liteorm.Session — pass either to any front-end. See Backends.

`orm.Repo[T]` — the declarative repository

repo := orm.NewRepo[T](sess). Full method surface (see ORM, soft delete):

Group	Methods
Create	`Create` · `CreateInBatches(vs, n)`
Insert-or-update	`Save` (by identity) · `Upsert(v, query.OnConflict(...).DoUpdate(...))` · `FirstOrCreate(v, conds...)` · `FirstOrInit(v, conds...)` (no write)
Read by key	`Get(keys...)` (→ `ErrNoRows`) · `GetByKeys(keys...)` (batch, single-PK)
Read (scoped)	`Find` · `First` · `Count` · `Exists` · `FindInBatches(n, fn)`
Read scopes (chain, return a view)	`Where` · `Filter(preds...)` · `OrderBy` · `Limit` · `Offset` · `Scopes(...)` · `IncludeDeleted` · `OnlyDeleted`
Update	`Update` · `Updates(v, cols...)` (partial)
Delete	`Delete` · `ForceDelete` · `Restore` (un-soft-delete)
Write scoping (return a view)	`Select(cols...)` · `Omit(cols...)`

Keyed Update/Delete/Restore return liteorm.ErrNoRows when no row matches. Create/Update/Delete fire hooks.

Associations (orm)

orm.Load[P, C](ctx, sess, parents, "Field", opts...) — one batched query, N+1-safe; opts: LoadWhere("...", args...), LoadOrderBy("..."). Nested: orm.LoadPath[P](ctx, sess, roots, "A.B") or orm.NewPreloader[P](sess).With("A").With("B.C").Load(ctx, roots). Write the non-owner side with orm.Assoc[P, C](sess, "Field", &owner) → Append/Delete/Replace/Clear/Count; m2m primitives orm.Attach/orm.Detach. See Associations.

Schema & migrations

orm.AutoMigrate[T](ctx, sess, orm.WithForeignKeys())   // one model (opt-in FK constraints)
orm.AutoMigrateAll(ctx, sess, A{}, B{}, C{})           // a whole set, in dependency order

Reviewable changes: orm.Diff[T] → Changes{Added, Removed, Changed}; orm.GenerateMigration[T] → up/down SQL (executes nothing). Introspect: orm.IntrospectColumns / IntrospectIndexes / IntrospectTables. Runner — migrate.New(sess) → Up/UpTo/Down/DownTo/Status/Version/Force; migrate.Load(fs.FS); migrate.WritePair(dir, ver, name, up, down). See Migrations.

`query` — the explicit builder

query.Select[T](sess) then a terminal (see Query builder):

Group	Surface
Terminals	`All` · `First` · `Count` · `Exists` · `Iter` (stream, `iter.Seq2`)
Filter / order / page	`Where(frag, args...)` · `Filter(preds...)` · `OrderBy` / `Order(Asc/Desc/OrderExpr)` · `Limit` · `Offset` · `Distinct` / `DistinctOn`
Joins	`InnerJoin` · `LeftJoin` · `RightJoin` · `CrossJoin` · `Join` · `JoinSub` · `JoinLateral`
Group	`GroupBy` / `GroupByCols` · `Having`
Set ops	`Union` / `UnionAll` · `Intersect`(`All`) · `Except`(`All`)
Locking	`ForUpdate` · `ForShare` · `SkipLocked` · `NoWait`
CTE / subquery source	`With` · `WithRecursive` · `From` · `query.FromSubquery`
Project / scalar	`Project` · `query.Pluck(ctx, b, col)` → `[]V` · `query.Into[T,R](ctx, b, fields...)`
Aggregates	`query.Sum/Avg/Min/Max/CountCol(ctx, b, col)` · `SumAs`/`AvgAs`/… in `Into`
Window / scalar subq	`RowNumber`/`Rank`/`DenseRank`/`Lag`/`Lead`/`WindowSum`…`.Over(...)` · `ScalarSubquery`

Predicates: query.Col[V]("col").Eq/Ne/Gt/Ge/Lt/Le/In/NotIn/Like/IsNull/IsNotNull · query.And/Or/Not · Exists/NotExists · Postgres query.JSON(...) / query.Array[E](...).

CRUD: query.NewRepo[T](sess) → Insert · InsertMany (bulk) · Get · Find(preds...) · Update · Delete · Upsert. Multi-row writes: query.Update[T](sess).Set/SetExpr(...).Where/Filter(...).Exec(ctx) (returns affected count) and query.Delete[T](sess)...Exec. Escape hatch: query.Raw[T](ctx, sess, sql, args...).

Errors

liteorm.ErrNoRows · ErrUniqueViolation · ErrForeignKey · ErrNotNull · ErrCheck · ErrDeadlock · ErrSerialization

Test with errors.Is(err, …) or the helpers: liteorm.IsUniqueViolation · IsForeignKeyViolation · IsNotNullViolation · IsCheckViolation · IsNotFound · IsRetryable (deadlock/serialization). See Errors.