Map Types

Maps store key-value pairs with specified key and value types.

Usage

interface User {  preferences: Record<string, string>;     // Map(String, String)  metrics: Record<string, number>;         // Map(String, Float64)  settings: Record<string, boolean>;       // Map(String, Boolean)}

Type Mapping Reference

ClickHouse Type	TypeScript	Python
`Map(String, String)`	`Record<string, string>`	`Dict[str, str]`
`Map(String, Float64)`	`Record<string, number>`	`Dict[str, float]`
`Map(String, Int64)`	`Record<string, Int64>`	`Dict[str, int]`
`Map(String, Boolean)`	`Record<string, boolean>`	`Dict[str, bool]`

Key types

Map keys must be String, Int*, or UInt* types. String keys are most common.

When to use Map vs JSON

Use Map when all values have the same type and you need efficient key lookups. Use JSON when values have mixed types or the structure is highly dynamic.

Map Types

Maps store key-value pairs with specified key and value types.

Usage

interface User {  preferences: Record<string, string>;     // Map(String, String)  metrics: Record<string, number>;         // Map(String, Float64)  settings: Record<string, boolean>;       // Map(String, Boolean)}

interface User {  preferences: Record<string, string>;     // Map(String, String)  metrics: Record<string, number>;         // Map(String, Float64)  settings: Record<string, boolean>;       // Map(String, Boolean)}

Type Mapping Reference

ClickHouse Type	TypeScript	Python
`Map(String, String)`	`Record<string, string>`	`Dict[str, str]`
`Map(String, Float64)`	`Record<string, number>`	`Dict[str, float]`
`Map(String, Int64)`	`Record<string, Int64>`	`Dict[str, int]`
`Map(String, Boolean)`	`Record<string, boolean>`	`Dict[str, bool]`

Key types

Map keys must be String, Int*, or UInt* types. String keys are most common.

When to use Map vs JSON

Use Map when all values have the same type and you need efficient key lookups. Use JSON when values have mixed types or the structure is highly dynamic.