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README.md

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+# gormcol
+
+Type-safe GORM column descriptors and model generation utilities.
+
+## Library
+
+Define struct-like variables mapping Go field names to `table.column` pairs:
+
+```go
+var PsAccess = struct {
+    IDProfile           gormcol.Field
+    IDAuthorizationRole gormcol.Field
+}{
+    IDProfile:           gormcol.Field{Table: "ps_access", Column: "id_profile"},
+    IDAuthorizationRole: gormcol.Field{Table: "ps_access", Column: "id_authorization_role"},
+}
+```
+
+Use the three accessor functions to extract column and table names without string literals:
+
+```go
+gormcol.Column(PsAccess.IDAuthorizationRole)      // "id_authorization_role"
+gormcol.ColumnOnTable(PsAccess.IDAuthorizationRole) // "ps_access.id_authorization_role"
+gormcol.TableField(PsAccess.IDAuthorizationRole)   // "ps_access"
+```
+
+## CLI
+
+The `cmd/` directory contains a standalone tool that generates GORM model files with column descriptors.
+
+### Install
+
+```bash
+go install git.ma-al.com/goc_marek/gormcol/cmd@latest
+```
+
+### Usage
+
+```
+gormcol-gen --dsn <connection-string> [options]
+```
+
+| Flag | Default | Description |
+|------|---------|-------------|
+| `--dsn` | *(required)* | MySQL/MariaDB DSN, e.g. `user:pass@tcp(localhost:3306)/dbname` |
+| `--filter` | `(ps_\|b2b_).*` | Regex matching table names to generate |
+| `--out` | `./app/model/prestadb` | Output directory for generated files |
+| `--pkg` | `prestadb` | Go package name for generated files |
+
+### Example
+
+```bash
+./gormcol-gen --dsn "user:pass@tcp(localhost:3306)/mydb" --filter "ps_.*" --out ./internal/model --pkg model
+```
+
+This connects to the database, generates a `.go` model file for each matching table, and appends `<Model>Cols` variables with typed `gormcol.Field` descriptors to each file.
+
+## Using generated models
+
+After generation, each model file contains a struct and a `Cols` variable:
+
+```go
+// model/product.go
+type Product struct {
+    ID    uint   `gorm:"column:id_product;primaryKey"`
+    Name  string `gorm:"column:name"`
+    Price float32 `gorm:"column:price;type:decimal(20,6)"`
+}
+
+var ProductCols = struct {
+    ID    Field
+    Name  Field
+    Price Field
+}{
+    ID:    Field{Table: "ps_product", Column: "id_product"},
+    Name:  Field{Table: "ps_product", Column: "name"},
+    Price: Field{Table: "ps_product", Column: "price"},
+}
+```
+
+### GORM queries with type-safe columns
+
+Use `ColumnOnTable` for table-qualified column references in GORM clauses:
+
+```go
+import "git.ma-al.com/goc_marek/gormcol"
+
+// Where clauses
+db.Where(
+    gormcol.ColumnOnTable(model.ProductCols.Price) + " > ?",
+    100.0,
+).Find(&products)
+
+// Order
+db.Order(gormcol.ColumnOnTable(model.ProductCols.Name) + " ASC").Find(&products)
+
+// Joins
+db.Joins("JOIN ps_category ON " +
+    gormcol.ColumnOnTable(model.ProductCols.ID) + " = ps_category.id_product",
+).Find(&products)
+```
+
+### Unqualified column names
+
+Use `Column` when the table is already scoped:
+
+```go
+db.Select(gormcol.Column(model.ProductCols.Name)).Find(&products)
+
+// Raw queries
+db.Raw("SELECT " + gormcol.Column(model.ProductCols.Name) + " FROM ps_product").Scan(&names)
+```
+
+### Table name
+
+Use `TableField` to get the table name from a column descriptor:
+
+```go
+table := gormcol.TableField(model.ProductCols.ID) // "ps_product"
+```
+
+## Dependencies
+
+- `gorm.io/gorm`
+- `gorm.io/gen`
+- `gorm.io/driver/mysql`