Documentation
¶
Overview ¶
Package clickhouse provides implementation of Clickhouse data warehouse
Index ¶
- Constants
- func GetOrderBy(schema *arrow.Schema) []string
- func GetPartitionBy(schema *arrow.Schema) string
- func NewClickHouseQueryMapper(opts ...Options) warehouse.QueryMapper
- func NewClickHouseTableDriver(chOptions *clickhouse.Options, database string, opts ...Options) (warehouse.Driver, error)
- func NewFieldTypeMapper() warehouse.FieldTypeMapper[SpecificClickhouseType]
- func SetOrderBy(schema *arrow.Schema, columns []string) *arrow.Schema
- func SetPartitionBy(schema *arrow.Schema, expr string) *arrow.Schema
- type Options
- type SpecificClickhouseType
Constants ¶
const ( // MetaOrderBy is the Arrow schema metadata key for a comma-separated list of // ORDER BY columns for ClickHouse table creation. // Example value: "toDate(timestamp), session_id" MetaOrderBy = "d8a.warehouse.clickhouse.order_by" // MetaPartitionBy is the Arrow schema metadata key for the PARTITION BY expression // for ClickHouse table creation. // Example value: "toYYYYMM(timestamp)" MetaPartitionBy = "d8a.warehouse.clickhouse.partition_by" )
Metadata keys for per-table ClickHouse DDL hints stored in Arrow schema metadata. These allow callers to override the driver-level ORDER BY and PARTITION BY defaults on a per-schema basis without changing the warehouse.Driver interface.
const ( // PrecisionMetadataKey is the metadata key used to store precision information for DateTime64 types PrecisionMetadataKey = "clickhouse.precision" // PrecisionMetadataValueSecond is the value indicating second precision for DateTime64 types PrecisionMetadataValueSecond = "0" )
const ClickhouseMapperName = "clickhouse"
ClickhouseMapperName is the name of the ClickHouse type mapper
Variables ¶
This section is empty.
Functions ¶
func GetOrderBy ¶ added in v0.52.0
GetOrderBy reads the ORDER BY columns from Arrow schema metadata. Returns nil if the key is absent or the value is empty.
func GetPartitionBy ¶ added in v0.52.0
GetPartitionBy reads the PARTITION BY expression from Arrow schema metadata. Returns empty string if the key is absent.
func NewClickHouseQueryMapper ¶
func NewClickHouseQueryMapper(opts ...Options) warehouse.QueryMapper
NewClickHouseQueryMapper creates a new ClickHouse query mapper.
func NewClickHouseTableDriver ¶
func NewClickHouseTableDriver( chOptions *clickhouse.Options, database string, opts ...Options, ) (warehouse.Driver, error)
NewClickHouseTableDriver creates a new ClickHouse table driver.
func NewFieldTypeMapper ¶
func NewFieldTypeMapper() warehouse.FieldTypeMapper[SpecificClickhouseType]
NewFieldTypeMapper creates a mapper that supports all ClickHouse types with proper circular dependency handling
func SetOrderBy ¶ added in v0.52.0
SetOrderBy returns a new *arrow.Schema with the ClickHouse ORDER BY hint set. The columns are joined with ", " in the DDL; pass them individually. Existing schema metadata is preserved.
Types ¶
type Options ¶
type Options func(*clickhouseQueryMapper)
Options represents a configuration option for ClickHouse query mapper.
func WithEngine ¶
WithEngine sets the engine type for ClickHouse tables.
func WithIndexGranularity ¶
WithIndexGranularity sets the index granularity for ClickHouse tables.
func WithOrderBy ¶
WithOrderBy sets the order by columns for ClickHouse tables.
func WithPartitionBy ¶
WithPartitionBy sets the partition expression for ClickHouse tables.
type SpecificClickhouseType ¶
type SpecificClickhouseType struct {
TypeAsString string
ColumnModifiers string // e.g., "DEFAULT" for nullable fields stored as NOT NULL with DEFAULT
DefaultValue any // Go-level default value for this type (nil if not applicable)
DefaultSQLExpression string // SQL expression for DEFAULT clause (e.g., "”", "0", "'1970-01-01'")
FormatFunc func(i any, m arrow.Metadata) (any, error)
}
SpecificClickhouseType represents a ClickHouse data type with its string representation and formatting function
Source Files