Github user liuyu000 commented on a diff in the pull request:
https://github.com/apache/incubator-trafodion/pull/1229#discussion_r138540283
--- Diff: docs/lob_guide/src/asciidoc/_chapters/about.adoc ---
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+////
+/**
+* @@@ START COPYRIGHT @@@
+*
+* Licensed to the Apache Software Foundation (ASF) under one
+* or more contributor license agreements. See the NOTICE file
+* distributed with this work for additional information
+* regarding copyright ownership. The ASF licenses this file
+* to you under the Apache License, Version 2.0 (the
+* "License"); you may not use this file except in compliance
+* with the License. You may obtain a copy of the License at
+*
+* http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing,
+* software distributed under the License is distributed on an
+* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+* KIND, either express or implied. See the License for the
+* specific language governing permissions and limitations
+* under the License.
+*
+* @@@ END COPYRIGHT @@@
+*/
+////
+
+[[About_This_Document]]
+= About This Document
+This guide dwscribes how to use Large Object (LOB) datatypes.
+
+[[Intended_Audience]]
+== Intended Audience
+This manual is intended for programmers who use LOB datatypes.
+
+[[New_and_Changed_Information]]
+== New and Changed Information
+This is a new guide.
+
+[[Document_Organization]]
+== Document Organization
+
+[cols="30%,70%",options="header"]
+|===
+|Chapter | Description
+| <<Introduction,Introduction>> | Introduces LOB and covers
following topics: +
+• 1.1 <<what is lob,What is LOB>> +
+• 1.2 <<lob data types,LOB Data Types>> +
+• 1.3 <<lob storage,LOB Storage>> +
+• 1.4 <<lob handle,LOB Handle>> +
+• 1.5 <<lob restrictions,LOB Restrictions>> +
+• 1.6 <<lob related sql statements and functions,LOB Related SQL
Statements and Functions>>.
+
+| <<Work with LOB,Work with LOB>> | Explains how to use LOB
with SQL statement and covers following topics: +
+• 2.1 <<create a sql table with lob columns,Create a SQL Table with
LOB Columns>> +
+• 2.2 <<insert into a sql table containing lob columns,Insert into
a SQL Table Containing LOB Columns>> +
+• 2.3 <<insert into a sql table containing lob columns using select
clause,Insert into a SQL Table Containing LOB Columns Using Select Clause>> +
+• 2.4 <<update a sql table containing lob columns,Update a SQL
Table Containing LOB Columns>> +
+• 2.5 <<select column from a sql table containing lob
columns,Select Column from a SQL Table Containing LOB Columns>> +
+• 2.6 <<extract lob data from a sql table containing lob
columns,Extract LOB Data from a SQL Table Containing LOB Columns>> +
+• 2.7 <<delete column from a sql table containing lob
columns,Delete Column from a SQL Table Containing LOB columns>> +
+• 2.8 <<drop a sql table containing lob columns,Drop a SQL Table
Containing LOB Columns>> +
+• 2.9 <<garbage collection,Garbage Collection>> +
+• 2.10 <<cleanup of a sql table containing lob columns,Cleanup of a
SQL Table Containing LOB Columns>> +
+• 2.11 <<showddl for lob,SHOWDDL for LOB>> +
+• 2.12 <<get command for lob tables,Get Command for LOB Tables>>
+|===
+
+== Notation Conventions
+This list summarizes the notation conventions for syntax presentation in
this manual.
+
+* UPPERCASE LETTERS
++
+Uppercase letters indicate keywords and reserved words. Type these items
exactly as shown. Items not enclosed in brackets are required.
++
+```
+SELECT
+```
+
+* lowercase letters
++
+Lowercase letters, regardless of font, indicate variable items that you
supply. Items not enclosed in brackets are required.
++
+```
+file-name
+```
+
+* [ ] Brackets
++
+Brackets enclose optional syntax items.
++
+```
+DATETIME [start-field TO] end-field
+```
++
+A group of items enclosed in brackets is a list from which you can choose
one item or none.
++
+The items in the list can be arranged either vertically, with aligned
brackets on each side of the list, or horizontally, enclosed in a pair of
brackets and separated by vertical lines.
++
+For example:
++
+```
+DROP SCHEMA schema [CASCADE]
+DROP SCHEMA schema [ CASCADE | RESTRICT ]
+```
+
+<<<
+* { } Braces
++
+Braces enclose required syntax items.
++
+```
+FROM { grantee [, grantee ] ... }
+```
++
+A group of items enclosed in braces is a list from which you are required
to choose one item.
++
+The items in the list can be arranged either vertically, with aligned
braces on each side of the list, or horizontally, enclosed in a pair of braces
and separated by vertical lines.
++
+For example:
++
+```
+INTERVAL { start-field TO end-field }
+{ single-field }
+INTERVAL { start-field TO end-field | single-field }
+```
+* | Vertical Line
++
+A vertical line separates alternatives in a horizontal list that is
enclosed in brackets or braces.
++
+```
+{expression | NULL}
+```
+* … Ellipsis
++
+An ellipsis immediately following a pair of brackets or braces indicates
that you can repeat the enclosed sequence of syntax items any number of times.
++
+```
+ATTRIBUTE[S] attribute [, attribute] ...
+{, sql-expression } ...
+```
++
+An ellipsis immediately following a single syntax item indicates that you
can repeat that syntax item any number of times.
++
+For example:
++
+```
+expression-n ...
+```
+
+* Punctuation
++
+Parentheses, commas, semicolons, and other symbols not previously
described must be typed as shown.
++
+```
+DAY (datetime-expression)
+@script-file
+```
++
+Quotation marks around a symbol such as a bracket or brace indicate the
symbol is a required character that you must type as shown.
++
+For example:
++
+```
+"{" module-name [, module-name] ... "}"
+```
+
+* Item Spacing
++
+Spaces shown between items are required unless one of the items is a
punctuation symbol such as a parenthesis or a comma.
++
+```
+DAY (datetime-expression) DAY(datetime-expression)
+```
++
+If there is no space between two items, spaces are not permitted. In this
example, no spaces are permitted between the period and any other items:
++
+```
+myfile.sh
+```
+
+* Line Spacing
++
+If the syntax of a command is too long to fit on a single line, each
continuation line is indented three spaces and is separated from the preceding
line by a blank line.
++
+This spacing distinguishes items in a continuation line from items in a
vertical list of selections.
++
+```
+match-value [NOT] LIKE _pattern
+ [ESCAPE esc-char-expression]
+```
+
+== Comments Encouraged
+We encourage your comments concerning this document. We are committed to
providing documentation that meets your
+needs. Send any errors found, suggestions for improvement, or compliments
to [email protected].
--- End diff --
Yes, hope we could get more and more encouragements. :)
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