From b7aa7eae302058eae81e9d51e9953460521b77b8 Mon Sep 17 00:00:00 2001 From: Micah Kornfield Date: Sun, 10 Apr 2016 04:46:14 +0000 Subject: [PATCH] change list offset array to offset buffer --- format/Layout.md | 22 +++++----------------- 1 file changed, 5 insertions(+), 17 deletions(-) diff --git a/format/Layout.md b/format/Layout.md index 20b003349224b..d7f1505061155 100644 --- a/format/Layout.md +++ b/format/Layout.md @@ -212,7 +212,7 @@ A list type is specified like `List`, where `T` is any relative type A list-array is represented by the combination of the following: * A values array, a child array of type T. T may also be a nested type. -* An offsets array containing 32-bit signed integers with length equal to the +* An offsets buffer containing 32-bit signed integers with length equal to the length of the top-level array plus one. Note that this limits the size of the values array to 2^31 -1. @@ -247,10 +247,7 @@ will have the following representation: |--------------------------|-----------------------| | 00001101 | 0 (padding) | -* Offsets array (int32 array) - * Length: 5, Null count: 0 - * Null bitmap buffer: Not required - * Value Buffer (offsets into the Values array): +* Offsets buffer (int32) | Bytes 0-3 | Bytes 4-7 | Bytes 8-11 | Bytes 12-15 | Bytes 16-19 | |------------|-------------|-------------|-------------|-------------| @@ -274,10 +271,7 @@ will be be represented as follows: * Length 3 * Nulls count: 0 * Null bitmap buffer: Not required -* Offsets array (int32 array) - * Length: 4, Null count: 0 - * Null bitmap buffer: Not required - * Value Buffer (offsets into the Values array): +* Offsets buffer (int32) | Bytes 0-3 | Bytes 4-7 | Bytes 8-11 | Bytes 12-15 | |------------|------------|------------|-------------| @@ -291,9 +285,7 @@ will be be represented as follows: |--------------------------|-------------| | 00110111 | 0 (padding) | - * Offsets array (int32 array) - * Length 7, Null count: 0 - * Null bitmap buffer: Not required + * Offsets buffer (int32) | Bytes 0-28 | |----------------------| @@ -440,7 +432,6 @@ An example layout for logical union of: |---------|-------------|----------|----------| | 0 | unspecified | 0 | 1 | - * Offset buffer: |Byte 0-3 | Byte 4-7 | Byte 8-11 | Byte 12-15 | @@ -537,10 +528,7 @@ will have the following layout: |--------------------------|-----------------------| | 00100100 | 0 (padding) | - * Offsets array (int32 array) - * Length: 7, Null count: 0 - * Null bitmap buffer: Not required - * Value Buffer (offsets into the Values array): + * Offsets buffer (int32) | Bytes 0-3 | Bytes 4-7 | Bytes 8-11 | Bytes 12-15 | Bytes 16-19 | Bytes 20-23 | Bytes 24-27 | |------------|-------------|-------------|-------------|-------------|-------------|-------------|