src/db/BuildSql.php
public function field($field = '*')
    {

        if (!$field) {
            return $this;
        }

        $this->options['field'] = is_array($field) ? $field : explode(',', $field);

        $this->bulid['field'] = '';
        foreach ($this->options['field'] as $val) {
            $this->bulid['field'] .= $this->addFieldTag($val) . ',';
        }

        $this->bulid['field'] = substr($this->bulid['field'], 0, -1);

        return $this;
    }
public function field($field = '*')
    {

        if (!$field) {
            return $this;
        }

        $this->options['field'] = is_array($field) ? $field : explode(',', $field);

        $this->bulid['field'] = '';
        foreach ($this->options['field'] as $val) {
            $this->bulid['field'] .= $this->addFieldTag($val) . ',';
        }

        $this->bulid['field'] = substr($this->bulid['field'], 0, -1);

        return $this;
    }
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