v0.0.358

sq/builder.go

@@ -0,0 +1,71 @@
+package sq
+
+import (
+	"fmt"
+	"gogs.mikescher.com/BlackForestBytes/goext/exerr"
+	"reflect"
+	"strings"
+)
+
+func BuildUpdateStatement(q Queryable, tableName string, obj any, idColumn string) (string, PP, error) {
+	rval := reflect.ValueOf(obj)
+	rtyp := rval.Type()
+
+	params := PP{}
+
+	setClauses := make([]string, 0)
+
+	matchClause := ""
+
+	for i := 0; i < rtyp.NumField(); i++ {
+
+		rsfield := rtyp.Field(i)
+		rvfield := rval.Field(i)
+
+		if !rsfield.IsExported() {
+			continue
+		}
+
+		columnName := rsfield.Tag.Get("db")
+		if columnName == "" || columnName == "-" {
+			continue
+		}
+
+		if idColumn == columnName {
+			idValue, err := convertValueToDB(q, rvfield.Interface())
+			if err != nil {
+				return "", nil, err
+			}
+
+			matchClause = fmt.Sprintf("(%s = :%s)", columnName, params.Add(idValue))
+
+			continue
+		}
+
+		if rsfield.Type.Kind() == reflect.Ptr && rvfield.IsNil() {
+
+			setClauses = append(setClauses, fmt.Sprintf("%s = NULL", columnName))
+
+		} else {
+
+			val, err := convertValueToDB(q, rvfield.Interface())
+			if err != nil {
+				return "", nil, err
+			}
+
+			setClauses = append(setClauses, fmt.Sprintf("(%s = :%s)", columnName, params.Add(val)))
+
+		}
+	}
+
+	if len(setClauses) == 0 {
+		return "", nil, exerr.New(exerr.TypeSQLBuild, "no updates clauses found in object").Build()
+	}
+
+	if matchClause == "" {
+		return "", nil, exerr.New(exerr.TypeSQLBuild, "id column not found in object").Build()
+	}
+
+	//goland:noinspection SqlNoDataSourceInspection
+	return fmt.Sprintf("UPDATE %s SET %s WHERE %s", tableName, strings.Join(setClauses, ", "), matchClause), params, nil
+}