docs: missing documentation for HEX_ENCODE, HEX_DECODE_BINARY, TRY_HEX_DECODE_BINARY, BASE64_ENCODE, BASE64_DECODE_BINARY, and TRY_BASE64_DECODE_BINARY binary aliases

[sundy-li]

What's Missing

Six binary-typed function aliases registered in the Databend function registry have no documentation:

Alias	Primary function	Input → Output
HEX_ENCODE	TO_HEX	BINARY → STRING
HEX_DECODE_BINARY	FROM_HEX	STRING → BINARY
TRY_HEX_DECODE_BINARY	TRY_FROM_HEX	STRING → BINARY (NULL on error)
BASE64_ENCODE	TO_BASE64	BINARY → STRING
BASE64_DECODE_BINARY	FROM_BASE64	STRING → BINARY
TRY_BASE64_DECODE_BINARY	TRY_FROM_BASE64	STRING → BINARY (NULL on error)

Source File

/workspace/databend/src/query/functions/src/scalars/binary.rs

Relevant registrations:

.scalar_builder("to_hex")
    .aliases(&["hex", "hex_encode"])   // hex_encode: BINARY → STRING

.scalar_builder("from_hex")
    .aliases(&["unhex", "hex_decode_binary"])   // hex_decode_binary: STRING → BINARY

registry.register_aliases("try_from_hex", &["try_hex_decode_binary"]);

.scalar_builder("to_base64")
    .aliases(&["base64_encode"])   // base64_encode: BINARY → STRING

.scalar_builder("from_base64")
    .aliases(&["base64_decode_binary"])   // base64_decode_binary: STRING → BINARY

registry.register_aliases("try_from_base64", &["try_base64_decode_binary"]);

What They Do

These are binary-typed overloads of the existing hex/base64 string functions. The key distinction from the string variants (HEX, UNHEX, TO_BASE64, FROM_BASE64) is that these aliases operate on or return the BINARY data type rather than STRING, making them useful when working with raw binary data.

• HEX_ENCODE(binary) — hex-encodes a BINARY value to a hex STRING
• HEX_DECODE_BINARY(string) — decodes a hex STRING to BINARY; throws on invalid input
• TRY_HEX_DECODE_BINARY(string) — same as above but returns NULL on error
• BASE64_ENCODE(binary) — base64-encodes a BINARY value to a STRING
• BASE64_DECODE_BINARY(string) — decodes a base64 STRING to BINARY; throws on invalid input
• TRY_BASE64_DECODE_BINARY(string) — same as above but returns NULL on error

Suggested Doc Location

These aliases should be mentioned in the existing docs for their primary functions:

• HEX_ENCODE → /docs/en/sql-reference/20-sql-functions/06-string-functions/hex.md or the conversion to-hex.md
• HEX_DECODE_BINARY / TRY_HEX_DECODE_BINARY → /docs/en/sql-reference/20-sql-functions/06-string-functions/from-hex.md
• BASE64_ENCODE → /docs/en/sql-reference/20-sql-functions/06-string-functions/to-base64.md
• BASE64_DECODE_BINARY / TRY_BASE64_DECODE_BINARY → /docs/en/sql-reference/20-sql-functions/06-string-functions/from-base64.md