--- layout: docu title: Blob Functions --- This section describes functions and operators for examining and manipulating [`BLOB` values]({% link docs/1.3/sql/data_types/blob.md %}). | Name | Description | |:--|:-------| | [`arg1 || arg2`](#arg1--arg2) | Concatenates two strings, lists, or blobs. Any `NULL` input results in `NULL`. See also [`concat(arg1, arg2, ...)`](#concatvalue-) and [`list_concat(list1, list2)`]({% link docs/1.3/sql/functions/list.md %}#list_concatlist1-list2). | | [`base64(blob)`](#base64blob) | Converts a `blob` to a base64 encoded string. | | [`concat(value, ...)`](#concatvalue-) | Concatenates multiple strings, lists, or blobs. `NULL` inputs are skipped. See also [operator `||`](#arg1--arg2). | | [`decode(blob)`](#decodeblob) | Converts `blob` to `VARCHAR`. Fails if `blob` is not valid UTF-8. | | [`encode(string)`](#encodestring) | Converts the `string` to `BLOB`. Converts UTF-8 characters into literal encoding. | | [`from_base64(string)`](#from_base64string) | Converts a base64 encoded `string` to a character string (`BLOB`). | | [`from_binary(value)`](#from_binaryvalue) | Converts a `value` from binary representation to a blob. | | [`from_hex(value)`](#from_hexvalue) | Converts a `value` from hexadecimal representation to a blob. | | [`hex(blob)`](#hexblob) | Converts `blob` to `VARCHAR` using hexadecimal encoding. | | [`md5(blob)`](#md5blob) | Returns the MD5 hash of the `blob` as a `VARCHAR`. | | [`md5_number(blob)`](#md5_numberblob) | Returns the MD5 hash of the `blob` as a `HUGEINT`. | | [`octet_length(blob)`](#octet_lengthblob) | Number of bytes in `blob`. | | [`read_blob(source)`](#read_blobsource) | Returns the content from `source` (a filename, a list of filenames, or a glob pattern) as a `BLOB`. See the [`read_blob` guide]({% link docs/1.3/guides/file_formats/read_file.md %}#read_blob) for more details. | | [`repeat(blob, count)`](#repeatblob-count) | Repeats the `blob` `count` number of times. | | [`sha1(blob)`](#sha1blob) | Returns a `VARCHAR` with the SHA-1 hash of the `blob`. | | [`sha256(blob)`](#sha256blob) | Returns a `VARCHAR` with the SHA-256 hash of the `blob`. | | [`to_base64(blob)`](#to_base64blob) | Converts a `blob` to a base64 encoded string. | | [`to_hex(blob)`](#to_hexblob) | Converts `blob` to `VARCHAR` using hexadecimal encoding. | | [`unbin(value)`](#unbinvalue) | Converts a `value` from binary representation to a blob. | | [`unhex(value)`](#unhexvalue) | Converts a `value` from hexadecimal representation to a blob. | #### `arg1 || arg2`

| **Description** | Concatenates two strings, lists, or blobs. Any `NULL` input results in `NULL`. See also [`concat(arg1, arg2, ...)`](#concatvalue-) and [`list_concat(list1, list2)`]({% link docs/1.3/sql/functions/list.md %}#list_concatlist1-list2). | | **Example 1** | `'Duck' || 'DB'` | | **Result** | `DuckDB` | | **Example 2** | `[1, 2, 3] || [4, 5, 6]` | | **Result** | `[1, 2, 3, 4, 5, 6]` | | **Example 3** | `'\xAA'::BLOB || '\xBB'::BLOB` | | **Result** | `\xAA\xBB` | #### `base64(blob)`

| **Description** | Concatenates multiple strings, lists, or blobs. `NULL` inputs are skipped. See also [operator `||`](#arg1--arg2). | | **Example** | `concat('Hello', ' ', 'World')` | | **Result** | `Hello World` | #### `decode(blob)`

| **Description** | Returns the content from `source` (a filename, a list of filenames, or a glob pattern) as a `BLOB`. See the [`read_blob` guide]({% link docs/1.3/guides/file_formats/read_file.md %}#read_blob) for more details. | | **Example** | `read_blob('hello.bin')` | | **Result** | `hello\x0A` | #### `repeat(blob, count)`