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Add examples in doc

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Signed-off-by: frank chen <frank.chen021@outlook.com>
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frank chen 2021-12-03 11:27:41 +08:00
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docs/en/sql-reference/functions/encoding-functions.md
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@ -93,6 +93,8 @@ For [String](../../sql-reference/data-types/string.md) and [FixedString](../../s
Values of [Float](../../sql-reference/data-types/float.md) and [Decimal](../../sql-reference/data-types/decimal.md) types are encoded as their representation in memory. As we support little-endian architecture, they are encoded in little-endian. Zero leading/trailing bytes are not omitted.
Values of [UUID](../data-types/uuid.md) type are encoded as big-endian order string.
**Arguments**
- `arg` — A value to convert to hexadecimal. Types: [String](../../sql-reference/data-types/string.md), [UInt](../../sql-reference/data-types/int-uint.md), [Float](../../sql-reference/data-types/float.md), [Decimal](../../sql-reference/data-types/decimal.md), [Date](../../sql-reference/data-types/date.md) or [DateTime](../../sql-reference/data-types/datetime.md).
@ -147,6 +149,21 @@ Result:
└──────────────────┘
```
Query:
``` sql
SELECT lower(hex(toUUID('61f0c404-5cb3-11e7-907b-a6006ad3dba0'))) as big_endian_hex
```
Result:
``` text
┌─big_endian_hex───────────────────┐
│ 907ba6006ad3dba061f0c4045cb311e7 │
└──────────────────────────────────┘
```
## unhex {#unhexstr}
Performs the opposite operation of [hex](#hex). It interprets each pair of hexadecimal digits (in the argument) as a number and converts it to the byte represented by the number. The return value is a binary string (BLOB).
@ -224,6 +241,8 @@ For [String](../../sql-reference/data-types/string.md) and [FixedString](../../s
Values of [Float](../../sql-reference/data-types/float.md) and [Decimal](../../sql-reference/data-types/decimal.md) types are encoded as their representation in memory. As we support little-endian architecture, they are encoded in little-endian. Zero leading/trailing bytes are not omitted.
Values of [UUID](../data-types/uuid.md) type are encoded as big-endian order string.
**Arguments**
- `arg` — A value to convert to binary. [String](../../sql-reference/data-types/string.md), [FixedString](../../sql-reference/data-types/fixedstring.md), [UInt](../../sql-reference/data-types/int-uint.md), [Float](../../sql-reference/data-types/float.md), [Decimal](../../sql-reference/data-types/decimal.md), [Date](../../sql-reference/data-types/date.md), or [DateTime](../../sql-reference/data-types/datetime.md).
@ -280,6 +299,21 @@ Result:
└──────────────────────────────────────────────────────────────────┘
```
Query:
``` sql
SELECT lower(bin(toUUID('61f0c404-5cb3-11e7-907b-a6006ad3dba0'))) as big_endian_bin
```
Result:
``` text
┌─big_endian_bin───────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│ 10010000011110111010011000000000011010101101001111011011101000000110000111110000110001000000010001011100101100110001000111100111 │
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
```
## unbin {#unbinstr}
Interprets each pair of binary digits (in the argument) as a number and converts it to the byte represented by the number. The functions performs the opposite operation to [bin](#bin).