Applies to VAST Cluster 5.5.
Settings, variables and the search path, logging, PostgreSQL-compatible helpers, sort keys and type names.
Each function has its own page: syntax, what it does, NULLs and edge cases, examples with their output, how it runs in VAST, how to make it faster, limitations and errors, and similar functions. Names that the VAST Query Engine doesn't have are in all functions A-Z.
Session and diagnostics
| Function |
What it does |
| current_setting |
Read the value of a VAST Query Engine setting, such as default_order or search_path, by its name. |
| getvariable |
Read a session variable by its name; a name with no value returns NULL. |
| in_search_path |
Test whether a database and schema are in the VAST Query Engine's search path; returns a BOOLEAN, or NULL when either name is NULL. |
| nextval |
nextval and currval read a sequence, which can't be created on VAST Cluster 5.5; how they fail, and how to number rows or generate keys instead. |
| write_log |
Write a message to the VAST Query Engine's log from a query and return NULL or a value you choose, with the level, log_type and return_value options. |
Types
| Function |
What it does |
| pg_typeof |
Return the SQL type of a value or column as lower-case text, with the names for literals, NULL, lists, structs and maps. |
Sorting
| Function |
What it does |
| create_sort_key |
Build a BLOB from one or more values whose byte order follows a sort order (ASC or DESC, NULLS FIRST or NULLS LAST). |
Formatting
| Function |
What it does |
| pg_size_pretty |
Write a number of bytes for people to read, in binary units of 1,024 (KiB, MiB, GiB); the PostgreSQL-compatible name for format_bytes. |
See also