title: check if a record field contains a value using standard sql (Google BigQuery)
body: <p>For example, if I have a schema like this:</p>
  
  <pre><code>[{
      "name": "fullName",
      "type": "string",
      "mode": "required"
   },
   {
      "name": "children",
      "type": "record",
      "mode": "repeated",
      "fields": [
      {
          "name": "name",
          "type": "string",
          "mode": "nullable"
      },
      {
          "name": "gender",
          "type": "string",
          "mode": "nullable"
      },
      {
          "name": "age",
          "type": "integer",
          "mode": "nullable"
      }] 
  }]
  </code></pre>
  
  <p>where a person can have multiple children and children are stored in a repeated record and can be accessed with children.name, children.gender, and children.age.
  There might be multiple rows displayed for this person if this person has more than one child, but all of these rows shares one row number.</p>
  
  <p>I would like to select all rows from this table where one of the child's name in a row matches a certain value, I am thinking it might be something like children.name contains.</p>