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Binary functions and operators#

Примечание

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Binary operators#

The || operator performs concatenation.

Binary functions#

concat(binary1, ..., binaryN) → varbinary: Returns the concatenation of binary1, binary2, ..., binaryN. This function provides the same functionality as the SQL-standard concatenation operator (||).

length(binary) → bigint: Returns the length of binary in bytes.

lpad(binary, size, padbinary) → varbinary: Left pads binary to size bytes with padbinary. If size is less than the length of binary, the result is truncated to size characters. size must not be negative and padbinary must be non-empty.

rpad(binary, size, padbinary) → varbinary: Right pads binary to size bytes with padbinary. If size is less than the length of binary, the result is truncated to size characters. size must not be negative and padbinary must be non-empty.

substr(binary, start) → varbinary: Returns the rest of binary from the starting position start, measured in bytes. Positions start with 1. A negative starting position is interpreted as being relative to the end of the string.

substr(binary, start, length) → varbinary: Returns a substring from binary of length length from the starting position start, measured in bytes. Positions start with 1. A negative starting position is interpreted as being relative to the end of the string.

reverse(binary) → varbinary: Returns binary with the bytes in reverse order.

Base64 encoding functions#

The Base64 functions implement the encoding specified in RFC 4648.

from_base64(string) → varbinary#: Decodes binary data from the base64 encoded string.

to_base64(binary) → varchar#: Encodes binary into a base64 string representation.

from_base64url(string) → varbinary#: Decodes binary data from the base64 encoded string using the URL safe alphabet.

to_base64url(binary) → varchar#: Encodes binary into a base64 string representation using the URL safe alphabet.

from_base32(string) → varbinary#: Decodes binary data from the base32 encoded string.

to_base32(binary) → varchar#: Encodes binary into a base32 string representation.

Hex encoding functions#

from_hex(string) → varbinary#: Decodes binary data from the hex encoded string.

to_hex(binary) → varchar#: Encodes binary into a hex string representation.

Integer encoding functions#

from_big_endian_32(binary) → integer#: Decodes the 32-bit two’s complement big-endian binary. The input must be exactly 4 bytes.

to_big_endian_32(integer) → varbinary#: Encodes integer into a 32-bit two’s complement big-endian format.

from_big_endian_64(binary) → bigint#: Decodes the 64-bit two’s complement big-endian binary. The input must be exactly 8 bytes.

to_big_endian_64(bigint) → varbinary#: Encodes bigint into a 64-bit two’s complement big-endian format.

Floating-point encoding functions#

from_ieee754_32(binary) → real#: Decodes the 32-bit big-endian binary in IEEE 754 single-precision floating-point format. The input must be exactly 4 bytes.

to_ieee754_32(real) → varbinary#: Encodes real into a 32-bit big-endian binary according to IEEE 754 single-precision floating-point format.

from_ieee754_64(binary) → double#: Decodes the 64-bit big-endian binary in IEEE 754 double-precision floating-point format. The input must be exactly 8 bytes.

to_ieee754_64(double) → varbinary#: Encodes double into a 64-bit big-endian binary according to IEEE 754 double-precision floating-point format.

Hashing functions#

crc32(binary) → bigint#: Computes the CRC-32 of binary. For general purpose hashing, use xxhash64(), as it is much faster and produces a better quality hash.

md5(binary) → varbinary#: Computes the MD5 hash of binary.

sha1(binary) → varbinary#: Computes the SHA1 hash of binary.

sha256(binary) → varbinary#: Computes the SHA256 hash of binary.

sha512(binary) → varbinary#: Computes the SHA512 hash of binary.

spooky_hash_v2_32(binary) → varbinary#: Computes the 32-bit SpookyHashV2 hash of binary.

spooky_hash_v2_64(binary) → varbinary#: Computes the 64-bit SpookyHashV2 hash of binary.

xxhash64(binary) → varbinary#: Computes the xxHash64 hash of binary.

murmur3(binary) → varbinary#: Computes the 128-bit MurmurHash3 hash of binary.

SELECT murmur3(from_base64(„aaaaaa“)); – ba 58 55 63 55 69 b4 2f 49 20 37 2c a0 e3 96 ef

HMAC functions#

hmac_md5(binary, key) → varbinary#: Computes HMAC with MD5 of binary with the given key.

hmac_sha1(binary, key) → varbinary#: Computes HMAC with SHA1 of binary with the given key.

hmac_sha256(binary, key) → varbinary#: Computes HMAC with SHA256 of binary with the given key.

hmac_sha512(binary, key) → varbinary#: Computes HMAC with SHA512 of binary with the given key.