Couchbase query filtering by tag in an array - sql

Question

I have a author bucket. And in this bucket I keep the author infos and author's articles. I want to select the articles that have the tags I want from the author bucket.
I have tried this but I could not find how to do the filtering.
SELECT art.* FROM author AS a
UNNEST a.articles AS art
WHERE art.tags = 'History'
This is author bucket:
{
"about": {
"name": "sassa",
"userName": "sassatur"
},
"articles": [
{
"authorId": [
"8c7ba33e-0674-4d99-bfad-29d144028bc9"
],
"claps": [],
"comments": [],
"content": {
"articleType": "HTML",
"data": "My First Article"
},
"id": "71d6fa22-61be-4a93-8e86-8d569080da97",
"publishStatus": "UNLISTED",
"statistic": {
"articleId": "71d6fa22-61be-4a93-8e86-8d569080da97",
"views": [
1602683127039,
1602683148270
]
},
"tags": [
"Art, History"
],
"title": "Culture"
},
{
"authorId": [
"8c7ba33e-0674-4d99-bfad-29d144028bc9"
],
"claps": [],
"comments": [],
"content": {
"articleType": "HTML",
"data": "My First Article"
},
"id": "81d6fa22-63be-4a93-8e86-8d569080da97",
"publishStatus": "UNLISTED",
"statistic": {
"views": [
1602683127039,
1602683148270
]
},
"tags": [
"Art"
],
"title": "Culture"
}
],
"id": "8c7ba33e-0674-4d99-bfad-29d144028bc9",
}

Answer 1

Try using ANY/IN/SATISFIES, like so:
SELECT art.* FROM author AS a
UNNEST a.articles AS art
WHERE ANY x IN art.tags SATISFIES x == 'Art' END;
This works for 'Art' in your example, but not 'History' because of the way you are storing tags. It's an array, but it appears to have a single(?) item with comma-separated values. So, instead of "tags": ["Art,History"], I would recommend: "tags": ["Art","History"] instead, and then it will work.
However, if you are stuck with the comma-separate string, you can use SPLIT and ARRAY_CONTAINS as well:
SELECT art.* FROM author AS a
UNNEST a.articles AS art
WHERE ANY x IN art.tags SATISFIES ARRAY_CONTAINS(SPLIT(x,", "), 'History') END;