Bytes Functions and Operators​

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A sequence of bytes representing raw data.

Bytes can be represented as a literal using this syntax: b''.

db> 

select b'Hello, world';

{b'Hello, world'}

db> 

select b'Hello,\x20world\x01';

{b'Hello, world\x01'}

There are also some generic functions that can operate on bytes:

db> 

select contains(b'qwerty', b'42');

{false}

Bytes are rendered as base64-encoded strings in JSON. When you cast a bytes value into JSON, that's what you'll get. In order to cast a json value into bytes, it must be a base64-encoded string.

db> 

select <json>b'Hello Gel!';

{"\"SGVsbG8gRWRnZURCIQ==\""}

db> 

select <bytes>to_json("\"SGVsbG8gRWRnZURCIQ==\"");

{b'Hello Gel!'}

An enum for indicating integer value encoding.

This enum is used by the to_int16(), to_int32(), to_int64() and the to_bytes() (added in 4.0) converters working with bytes and integers.

Endian.Big stands for big-endian encoding going from most significant byte to least. Endian.Little stands for little-endian encoding going from least to most significant byte.

db> 

select to_bytes(<int32>16908295, Endian.Big);

{b'\x01\x02\x00\x07'}

db> 

select to_int32(b'\x01\x02\x00\x07', Endian.Big);

{16908295}

db> 

select to_bytes(<int32>16908295, Endian.Little);

{b'\x07\x00\x02\x01'}

db> 

select to_int32(b'\x07\x00\x02\x01', Endian.Little);

{16908295}

Accesses a byte at a given index.

Examples:

db> 

select b'binary \x01\x02\x03\x04 ftw!'[2];

{b'n'}

db> 

select b'binary \x01\x02\x03\x04 ftw!'[8];

{b'\x02'}

Produces a bytes sub-sequence from an existing bytes value.

Examples:

db> 

select b'\x01\x02\x03\x04 ftw!'[2:-1];

{b'\x03\x04 ftw'}

db> 

select b'some bytes'[2:-3];

{b'me by'}

Concatenates two bytes values into one.

db> 

select b'\x01\x02' ++ b'\x03\x04';

{b'\x01\x02\x03\x04'}

Converts a given value into binary representation as bytes.

The strings get converted using UTF-8 encoding:

db> 

select to_bytes('テキスト');

{b'\xe3\x83\x86\xe3\x82\xad\xe3\x82\xb9\xe3\x83\x88'}

The json values get converted as strings using UTF-8 encoding:

db> 

select to_bytes(to_json('{"a": 1}'));

{b'{"a": 1}'}

The integer values can be encoded as big-endian (most significant bit comes first) byte strings:

db> 

select to_bytes(<int16>31, Endian.Big);

{b'\x00\x1f'}

db> 

select to_bytes(<int32>31, Endian.Big);

{b'\x00\x00\x00\x1f'}

db> 

select to_bytes(123456789123456789, Endian.Big);

{b'\x01\xb6\x9bK\xac\xd0_\x15'}

The UUID values are converted to the underlying string of 16 bytes:

db> 

select to_bytes(<uuid>'1d70c86e-cc92-11ee-b4c7-a7aa0a34e2ae');

{b'\x1dp\xc8n\xcc\x92\x11\xee\xb4\xc7\xa7\xaa\n4\xe2\xae'}

To perform the reverse conversion there are corresponding functions: to_str(), to_int16(), to_int32(), to_int64(), to_uuid().

Returns the specified bit of the bytes value.

When looking for the nth bit, this function will enumerate bits from least to most significant in each byte.

db> 
... 
... 

for n in {0, 1, 2, 3, 4, 5, 6, 7,
          8, 9, 10, 11, 12, 13 ,14, 15}
union bytes_get_bit(b'ab', n);

{1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0}

Returns a Base64-encoded str of the bytes value.

db> 

select enc::base64_encode(b'hello');

{'aGVsbG8='}

Returns the bytes of a Base64-encoded str.

Returns an InvalidValueError if input is not valid Base64.

db> 

select enc::base64_decode('aGVsbG8=');

{b'hello'}

db> 

select enc::base64_decode('aGVsbG8');

gel error: InvalidValueError: invalid base64 end sequence