high memory usage caused by high cardinal column stringTagValue as primary key in tag_attributes

[srikanthccv]

CREATE TABLE signoz_traces.span_attributes
(
    `timestamp` DateTime CODEC(DoubleDelta, ZSTD(1)),
    `tagKey` LowCardinality(String) CODEC(ZSTD(1)),
    `tagType` Enum8('tag' = 1, 'resource' = 2) CODEC(ZSTD(1)),
    `dataType` Enum8('string' = 1, 'bool' = 2, 'float64' = 3) CODEC(ZSTD(1)),
    `stringTagValue` String CODEC(ZSTD(1)),
    `float64TagValue` Nullable(Float64) CODEC(ZSTD(1)),
    `isColumn` Bool CODEC(ZSTD(1))
)
ENGINE = ReplicatedReplacingMergeTree('/clickhouse/tables/{uuid}/{shard}', '{replica}')
ORDER BY (tagKey, tagType, dataType, stringTagValue, float64TagValue, isColumn)
TTL toDateTime(timestamp) + toIntervalSecond(172800)
SETTINGS index_granularity = 8192, ttl_only_drop_parts = 1, allow_nullable_key = 1

If certain has extremely high cardinal values (such as db.statement unsanitized with raw string), then the memory used to load the primary key index alone takes tens of GBs. We should not keep it as part of the primary key.

[srikanthccv]

Fixed in #487