"natural join" meaning in English

{
  "forms": [
    {
      "form": "natural joins",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "natural join (plural natural joins)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with French translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Greek translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Portuguese translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Databases",
          "orig": "en:Databases",
          "parents": [
            "Computing",
            "Technology",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A join between two tables on a field which has the same name."
      ],
      "hypernyms": [
        {
          "word": "join"
        }
      ],
      "id": "en-natural_join-en-noun-IdadqxmR",
      "links": [
        [
          "database",
          "database"
        ],
        [
          "join",
          "join"
        ]
      ],
      "raw_glosses": [
        "(databases) A join between two tables on a field which has the same name."
      ],
      "related": [
        {
          "word": "equijoin"
        },
        {
          "word": "inner join"
        }
      ],
      "topics": [
        "computing",
        "databases",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "sciences"
      ],
      "translations": [
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "join",
          "word": "luonnollinen liitos"
        },
        {
          "code": "fr",
          "lang": "French",
          "sense": "join",
          "word": "jointure naturelle"
        },
        {
          "code": "el",
          "lang": "Greek",
          "roman": "fysikí synénosi",
          "sense": "join",
          "word": "φυσική συνένωση"
        },
        {
          "code": "pt",
          "lang": "Portuguese",
          "sense": "join",
          "word": "junção natural"
        }
      ]
    }
  ],
  "word": "natural join"
}

{
  "forms": [
    {
      "form": "natural joins",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "natural join (plural natural joins)",
      "name": "en-noun"
    }
  ],
  "hypernyms": [
    {
      "word": "join"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "equijoin"
    },
    {
      "word": "inner join"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Finnish translations",
        "Terms with French translations",
        "Terms with Greek translations",
        "Terms with Portuguese translations",
        "en:Databases"
      ],
      "glosses": [
        "A join between two tables on a field which has the same name."
      ],
      "links": [
        [
          "database",
          "database"
        ],
        [
          "join",
          "join"
        ]
      ],
      "raw_glosses": [
        "(databases) A join between two tables on a field which has the same name."
      ],
      "topics": [
        "computing",
        "databases",
        "engineering",
        "mathematics",
        "natural-sciences",
        "physical-sciences",
        "sciences"
      ]
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "join",
      "word": "luonnollinen liitos"
    },
    {
      "code": "fr",
      "lang": "French",
      "sense": "join",
      "word": "jointure naturelle"
    },
    {
      "code": "el",
      "lang": "Greek",
      "roman": "fysikí synénosi",
      "sense": "join",
      "word": "φυσική συνένωση"
    },
    {
      "code": "pt",
      "lang": "Portuguese",
      "sense": "join",
      "word": "junção natural"
    }
  ],
  "word": "natural join"
}