Contents

• pg-base62
  • Types
    • base62
  • int4
  • base62
    • bigbase62
  • int8
  • bigbase62
    • hugebase62
  • hugebase62
  • bytea
  • hugebase62
    • Index support
  • Installation from source codes

pg-base62

Base62 extension for PostgreSQL. The extension provides data types to encode and decode values using base62 encoding scheme.

Base62 uses 62 ASCII characters: 0 - 9, A - Z and a - z.

More information about base62 encoding scheme: - Wikipedia page: https://en.wikipedia.org/wiki/Base62 - A blog post: https://helloacm.com/base62/

Types

base62

base62 stores encoded value in 4 bytes integer. The maximum length of string representation is 6 characters and maximum value of numeric representation is 2147483647.

```sql -- Cast from text =# select '2LKcb1'::base62::int;

int4

2147483647

-- Cast from integer =# select 2147483647::base62;

base62

2LKcb1

=# select '1111111'::base62::int; ERROR: value "1111111" is out of range for type base62

-- The type is case sensitive =# select '2lkcb'::base62::int, '2lkcb'::base62, '2LKCB'::base62::int, '2LKCB'::base62; int4 | base62 | int4 | base62 ----------+--------+----------+-------- 40933305 | 2lkcb | 34635195 | 2LKCB ```

bigbase62

bigbase62 stores encoded value in 8 bytes integer. The maxiumum length of string representation is 11 characters and the maximum value of numeric representation is 9223372036854775807.

```sql -- Cast from text =# select 'AzL8n0Y58m7'::bigbase62::bigint;

int8

9223372036854775807

-- Cast from integer =# select 9223372036854775807::bigbase62;

bigbase62

AzL8n0Y58m7

=# select '111111111111'::bigbase62::bigint; ERROR: value "111111111111" is out of range for type bigbase62

-- The type is case sensitive =# select '2lkcb1'::bigbase62::bigint, '2lkcb1'::bigbase62, '2LKCB1'::bigbase62::bigint, '2LKCB1'::bigbase62; int8 | bigbase62 | int8 | bigbase62 ------------+-----------+------------+----------- 2537864911 | 2lkcb1 | 2147382091 | 2LKCB1 ```

hugebase62

hugebase62 stores encoded value in 16 bytes integer. The maximum length of string representation is 20 characters.

It doesn't support casting from/to numeric type. Instead it support casting from/to bytea type. This is useful for applications to work with hugebase62.

```sql -- Cast from text =# select 'AzL8n0Y58m7AzL8n0Y58'::hugebase62;

hugebase62

AzL8n0Y58m7AzL8n0Y58

=# select 'AzL8n0Y58m7AzL8n0Y58'::hugebase62::bytea;

bytea

\x960c06065a6ed8ffff1e7149f40b1800

-- Cast from bytea =# select '\x960c06065a6ed8ffff1e7149f40b1800'::bytea::hugebase62;

hugebase62

AzL8n0Y58m7AzL8n0Y58

=# select '111111111111111111111'::hugebase62; ERROR: value "111111111111111111111" is out of range for type hugebase62

-- The type is case sensitive =# select '2lkcb1'::hugebase62::bytea, '2lkcb1'::hugebase62, '2LKCB1'::hugebase62::bytea, '2LKCB1'::hugebase62; bytea | hugebase62 | bytea | hugebase62 ------------------------------------+------------+------------------------------------+------------ \xcfbe4497000000000000000000000000 | 2lkcb1 | \x4b73fe7f000000000000000000000000 | 2LKCB1 ```

Index support

All types support btree and hash indexes.

Installation from source codes

To install base62, execute this in the extension's directory:

shell make install

Notice: Don't forget to set the PG_CONFIG variable (make PG_CONFIG=...) in case you want to test base62 on a non-default or custom build of PostgreSQL. Read more here.

Important: To compile base62 your compiler should support 128-bit integers, otherwise it will fail during compilation.