Chapter 22. MAP Data
Table of Contents
- 22.1. Retrieving the Size of MAP Data (
cardinality)- 22.2. Retrieving a Value from MAP Data (
map_extract_value)- 22.3. Retrieving a Value from MAP Data as a List (
map_extract)- 22.4. Concatenating MAP Values (
map_concat)- 22.5. Checking a MAP Key (
map_contains)- 22.6. Checking a MAP Key-Value Pair (
map_contains_entry)- 22.7. Checking a MAP Value (
map_contains_value)- 22.8. Retrieving Key-Value Pairs from MAP Data (
map_entries)- 22.9. Retrieving Keys from MAP Data (
map_keys)- 22.10. Retrieving Values from MAP Data (
map_values)- 22.11. Creating MAP Data from Key-Value Pairs (
map_from_entries)- 22.12. Creating Empty MAP Data (
map) - 22.2. Retrieving a Value from MAP Data (
MAP data is an ordered list of key-value pairs with a single key data type and a single value data type. The key data type does not need to match the value data type. Unlike STRUCT data, MAP does not require each row to contain the same keys. However, MAP data cannot contain duplicate keys and returns NULL for missing keys instead of an error.
This chapter describes stored procedures for querying and transforming MAP data.