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Add examples in docs

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avogar 2024-03-27 22:26:44 +00:00
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docs/en/sql-reference/data-types/variant.md
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@ -395,3 +395,37 @@ SELECT v, variantType(v) FROM test ORDER by v;
│ 100 │ UInt32 │
└─────┴────────────────┘
```
## JSONExtract functions with Variant
All `JSONExtract*` functions support `Variant` type:
```sql
SELECT JSONExtract('{"a" : [1, 2, 3]}', 'a', 'Variant(UInt32, String, Array(UInt32))') AS variant, variantType(variant) AS variant_type;
```
```text
┌─variant─┬─variant_type──┐
│ [1,2,3] │ Array(UInt32) │
└─────────┴───────────────┘
```
```sql
SELECT JSONExtract('{"obj" : {"a" : 42, "b" : "Hello", "c" : [1,2,3]}}', 'obj', 'Map(String, Variant(UInt32, String, Array(UInt32)))') AS map_of_variants, mapApply((k, v) -> (k, variantType(v)), map_of_variants) AS map_of_variant_types
```
```text
┌─map_of_variants──────────────────┬─map_of_variant_types────────────────────────────┐
│ {'a':42,'b':'Hello','c':[1,2,3]} │ {'a':'UInt32','b':'String','c':'Array(UInt32)'} │
└──────────────────────────────────┴─────────────────────────────────────────────────┘
```
```sql
SELECT JSONExtractKeysAndValues('{"a" : 42, "b" : "Hello", "c" : [1,2,3]}', 'Variant(UInt32, String, Array(UInt32))') AS variants, arrayMap(x -> (x.1, variantType(x.2)), variants) AS variant_types
```
```text
┌─variants───────────────────────────────┬─variant_types─────────────────────────────────────────┐
│ [('a',42),('b','Hello'),('c',[1,2,3])] │ [('a','UInt32'),('b','String'),('c','Array(UInt32)')] │
└────────────────────────────────────────┴───────────────────────────────────────────────────────┘
```