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README.md

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+# Pipeline Query Language
+
+This Go library compiles a pipeline-based query language
+(inspired by the [Kusto Query Language][])
+into SQL.
+It has been specifically tested to work with the [Clickhouse SQL dialect][],
+but the generated SQL is intentionally database agnostic.
+
+For example, something like:
+
+```plain
+StormEvents
+| where DamageProperty > 5000 and EventType == "Thunderstorm Wind"
+| top 3 by DamageProperty
+```
+
+will be compiled to:
+
+```sql
+SELECT *
+FROM StormEvents
+WHERE DamageProperty > 5000 and EventType == 'Thunderstorm Wind'
+ORDER BY DamageProperty DESC
+LIMIT 3;
+```
+
+[Kusto Query Language]: https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/
+[Clickhouse SQL dialect]: https://clickhouse.com/docs/en/sql-reference
+
+## Features
+
+The following tabular operators are supported:
+
+- [`count`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/count-operator)
+- [`project`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/project-operator)
+- [`sort`/`order`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/sort-operator)
+- [`summarize`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/summarize-operator)
+- [`take`/`limit`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/take-operator)
+- [`top`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/top-operator)
+- [`where`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/where-operator)
+
+The following functions are specifically handled.
+Functions not in this list will be passed through to the underlying SQL engine.
+
+- [`not`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/not-function)
+- [`isnull`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/isnull-function)
+  and [`isnotnull`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/isnotnull-function)
+- [`strcat`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/strcat-function)
+- [`iff`/`iif`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/iff-function)
+- [`count`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/count-aggregation-function)
+- [`countif`](https://learn.microsoft.com/en-us/azure/data-explorer/kusto/query/countif-aggregation-function)