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fix: remove string for supported tye for RLE encoding #400

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RaphDal merged 2 commits into from
Mar 27, 2026
+15 −17
Merged

fix: remove string for supported tye for RLE encoding #400

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4a48f70
docs: update Parquet SQL documentation to remove 'DROP' references
RaphDal Mar 27, 2026
e8dd9fe
docs: update encoding table in CREATE TABLE reference for clarity and…
RaphDal Mar 27, 2026
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2 changes: 1 addition & 1 deletion documentation/query/export-parquet.md
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Original file line number Diff line number Diff line change
Expand Up @@ -211,5 +211,5 @@ penalty of keeping pages that barely compress.
Individual columns can override the global encoding and compression settings.
See [CREATE TABLE - Per-column Parquet encoding and compression](/docs/query/sql/create-table/#per-column-parquet-encoding-and-compression)
for defining overrides at table creation, or
[ALTER TABLE ALTER COLUMN SET/DROP PARQUET](/docs/query/sql/alter-table-alter-column-parquet-encoding/)
[ALTER TABLE ALTER COLUMN SET PARQUET](/docs/query/sql/alter-table-alter-column-parquet-encoding/)
for modifying existing tables.
8 changes: 3 additions & 5 deletions documentation/query/sql/alter-table-alter-column-parquet-encoding.md
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@@ -1,7 +1,7 @@
---
title: ALTER TABLE ALTER COLUMN SET/DROP PARQUET
title: ALTER TABLE ALTER COLUMN SET PARQUET
sidebar_label: PARQUET ENCODING/COMPRESSION
description: ALTER TABLE ALTER COLUMN SET/DROP PARQUET SQL keyword reference documentation.
description: ALTER TABLE ALTER COLUMN SET PARQUET SQL keyword reference documentation.
---

Sets or removes per-column Parquet encoding and compression configuration on
Expand All @@ -27,12 +27,10 @@ ALTER TABLE sensors ALTER COLUMN temperature SET PARQUET(default, zstd(3));
ALTER TABLE sensors ALTER COLUMN temperature SET PARQUET(rle_dictionary, zstd(3));
```

## DROP

Reset per-column overrides back to the server defaults.

```questdb-sql title="Reset to defaults"
ALTER TABLE sensors ALTER COLUMN temperature DROP PARQUET;
ALTER TABLE sensors ALTER COLUMN temperature SET PARQUET(default);
```

## Supported encodings and codecs
Expand Down
22 changes: 11 additions & 11 deletions documentation/query/sql/create-table.md
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Expand Up @@ -387,12 +387,12 @@ the server-wide compression codec

#### Supported encodings

| Encoding | SQL keyword | Valid column types |
| ----------------------- | ------------------------- | ---------------------------- |
| Plain | `plain` | All |
| RLE Dictionary | `rle_dictionary` | All except BOOLEAN and ARRAY |
| Delta Length Byte Array | `delta_length_byte_array` | STRING, BINARY, VARCHAR |
| Delta Binary Packed | `delta_binary_packed` | INT, LONG, DATE, TIMESTAMP |
| Encoding | SQL keyword | Valid column types |
| ----------------------- | ------------------------- | ------------------------------------ |
| Plain | `plain` | All |
| RLE Dictionary | `rle_dictionary` | All except BOOLEAN, ARRAY AND STRING |
| Delta Length Byte Array | `delta_length_byte_array` | STRING, BINARY, VARCHAR |
| Delta Binary Packed | `delta_binary_packed` | INT, LONG, DATE, TIMESTAMP |

- **Plain** — stores values as-is with no transformation. Simplest encoding
with no overhead. Use as a fallback when data has high cardinality and no
Expand Down Expand Up @@ -452,7 +452,7 @@ For more details on Parquet compression, see the
[Apache Parquet compression documentation](https://parquet.apache.org/docs/file-format/data-pages/compression/).

To modify encoding or compression on existing tables, see
[ALTER TABLE ALTER COLUMN SET/DROP PARQUET](/docs/query/sql/alter-table-alter-column-parquet-encoding/).
[ALTER TABLE ALTER COLUMN SET PARQUET](/docs/query/sql/alter-table-alter-column-parquet-encoding/).

### Casting types

Expand Down Expand Up @@ -664,10 +664,10 @@ Checking the values per-table may be done using the `tables()` function:
SELECT id, table_name, maxUncommittedRows FROM tables();
```

| id | name | maxUncommittedRows |
| :-- | :----------- | :----------------- |
| 1 | trades | 250000 |
| 2 | sample_table | 50000 |
| id | name | maxUncommittedRows |
| :--- | :----------- | :----------------- |
| 1 | trades | 250000 |
| 2 | sample_table | 50000 |

## Table target volume

Expand Down
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