Option:  "WITH PARSER parser_name",
			Fields: []schema.IndexOption{{Field: &schema.Field{Name: "Name6"}}, {
				Field:      &schema.Field{Name: "Age"},
				Expression: "ABS(age)",
			}},
		},
		"idx_id": {
			Name:   "idx_id",
			Fields: []schema.IndexOption{{Field: &schema.Field{Name: "MemberNumber"}}, {Field: &schema.Field{Name: "OID", UniqueIndex: "idx_oid"}}},
		},
		"idx_oid": {
			Name:   "idx_oid",

			return
		}

		if db.Statement.Schema != nil {
			for _, c := range db.Statement.Schema.DeleteClauses {
				db.Statement.AddClause(c)
			}
		}

		if db.Statement.SQL.Len() == 0 {
			db.Statement.SQL.Grow(100)
			db.Statement.AddClauseIfNotExists(clause.Delete{})

			if db.Statement.Schema != nil {

				case reflect.Slice:
					queryFields = db.Statement.ReflectValue.Type().Elem() != db.Statement.Schema.ModelType
				}
			}

			if queryFields {
				stmt := gorm.Statement{DB: db}
				// smaller struct
				if err := stmt.Parse(db.Statement.Dest); err == nil && (db.QueryFields || stmt.Schema.ModelType != db.Statement.Schema.ModelType) {

					for _, field := range stmt.Schema.PrimaryFields {
						_, isZero = field.ValueOf(stmt.Context, stmt.ReflectValue.Index(i))
						if !isZero {
							break
						}
					}
				}

				if !isZero {
					_, primaryValues := schema.GetIdentityFieldValuesMap(stmt.Context, stmt.ReflectValue, stmt.Schema.PrimaryFields)
					column, values := schema.ToQueryValues("", stmt.Schema.PrimaryFieldDBNames, primaryValues)

	"gorm.io/gorm/clause"
	"gorm.io/gorm/schema"
	"gorm.io/gorm/utils"
)

// BeforeCreate before create hooks
func BeforeCreate(db *gorm.DB) {
	if db.Error == nil && db.Statement.Schema != nil && !db.Statement.SkipHooks && (db.Statement.Schema.BeforeSave || db.Statement.Schema.BeforeCreate) {
		callMethod(db, func(value interface{}, tx *gorm.DB) (called bool) {
			if db.Statement.Schema.BeforeSave {

			for _, rel := range dep.Schema.Relationships.Relations {
				if rel.Field.IgnoreMigration {
					continue
				}
				if c := rel.ParseConstraint(); c != nil && c.Schema == dep.Statement.Schema && c.Schema != c.ReferenceSchema {
					dep.Depends = append(dep.Depends, c.ReferenceSchema)
				}

				if rel.Type == schema.HasOne || rel.Type == schema.HasMany {
					beDependedOn[rel.FieldSchema] = true
				}

}

// ParseUniqueConstraints parse schema unique constraints
func (schema *Schema) ParseUniqueConstraints() map[string]UniqueConstraint {
	uniques := make(map[string]UniqueConstraint)
	for _, field := range schema.Fields {
		if field.Unique {
			name := schema.namer.UniqueName(schema.Table, field.DBName)
			uniques[name] = UniqueConstraint{Name: name, Field: field}
		}
	}

package callbacks

import (
	"fmt"
	"reflect"
	"sort"
	"strings"

	"gorm.io/gorm"
	"gorm.io/gorm/clause"
	"gorm.io/gorm/schema"
	"gorm.io/gorm/utils"
)

// parsePreloadMap extracts nested preloads. e.g.
//
//	// schema has a "k0" relation and a "k7.k8" embedded relation
//	parsePreloadMap(schema, map[string][]interface{}{
//		clause.Associations: {"arg1"},
//		"k1":                {"arg2"},
//		"k2.k3":             {"arg3"},

	Length     int
	priority   int
}

// ParseIndexes parse schema indexes
func (schema *Schema) ParseIndexes() map[string]Index {
	indexes := map[string]Index{}

	for _, field := range schema.Fields {
		if field.TagSettings["INDEX"] != "" || field.TagSettings["UNIQUEINDEX"] != "" {
			fieldIndexes, err := parseFieldIndexes(field)
			if err != nil {
				schema.err = err
				break
			}
			for _, index := range fieldIndexes {

Wenn Sie zur API-Dokumentation gehen, werden Sie sehen, dass diese die **Schemas** für die Daten enthält, welche in Requests gesendet und in Responses empfangen werden:

<img src="/img/tutorial/generate-clients/image01.png">

Sie können diese Schemas sehen, da sie mit den Modellen in der Anwendung deklariert wurden.