*: add TiDB basic features and update overview (#2999)

* *: add TiDB basic features and update overview

* Update a link

* Update overview to new content

* Apply suggestions from code review

Co-authored-by: Ran <huangran@pingcap.com>

* Update description and terms

* Update wording

* Add TiDB Cloud descriptions to features

* Update em dash

* Add one word "specifically"

* Apply iamxy's suggestion

* Add cloud descriptions to index

* Update para format

* Change para format back

* Apply suggestions from code review

Co-authored-by: Keke Yi <40977455+yikeke@users.noreply.github.com>

Co-authored-by: Ran <huangran@pingcap.com>
Co-authored-by: Keke Yi <40977455+yikeke@users.noreply.github.com>

TOC.md

@@ -8,7 +8,7 @@
 + About TiDB
   + [TiDB Introduction](/overview.md)
   + [What's New in TiDB 4.0](/whats-new-in-tidb-4.0.md)
-  + [Key Features](/key-features.md)
+  + [Basic Features](/basic-features.md)
   + Compatibility
     + [MySQL Compatibility](/mysql-compatibility.md)
   + [TiDB Limitations](/tidb-limitations.md)

_index.md

@@ -1,20 +1,22 @@
 ---
 title: TiDB Introduction
-summary: Learn how to quickly start a TiDB cluster.
+summary: Learn about the NewSQL database TiDB that supports HTAP workloads.
 category: introduction
 aliases: ['/docs/dev/']
 ---
 
 # TiDB Introduction
 
-[TiDB](https://github.com/pingcap/tidb) ("Ti" stands for Titanium) is an open-source NewSQL database that supports Hybrid Transactional and Analytical Processing (HTAP) workloads. It is MySQL compatible and features horizontal scalability, strong consistency, and high availability. TiDB can be deployed on-premise or in-cloud.
+[TiDB](https://github.com/pingcap/tidb) ("Ti" stands for Titanium) is an open-source, distributed, NewSQL database that supports Hybrid Transactional and Analytical Processing (HTAP) workloads. It is MySQL compatible and features horizontal scalability, strong consistency, and high availability. TiDB can be deployed on-premise or in-cloud.
+
+Designed for the cloud, TiDB provides flexible scalability, reliability and security on the cloud platform. Users can elastically scale TiDB to meet the requirements of their changing workloads. [TiDB Operator](https://docs.pingcap.com/tidb-in-kubernetes/v1.1/tidb-operator-overview) helps manage TiDB on Kubernetes and automates operating tasks, which makes TiDB easier to deploy on any cloud that provides managed Kubernetes. [TiDB Cloud](https://pingcap.com/products/tidbcloud) (Beta), the fully-managed TiDB service, is the easiest, most economical, and most resilient way to unlock the full power of [TiDB in the cloud](https://docs.pingcap.com/tidbcloud/beta), allowing you to deploy and run TiDB clusters with just a few clicks.
 
 <NavColumns>
 <NavColumn>
 <ColumnTitle>About TiDB</ColumnTitle>
 
 - [TiDB Introduction](/overview.md)
-- [Key Features](/key-features.md)
+- [Basic Features](/basic-features.md)
 - [Compatibility with MySQL](/mysql-compatibility.md)
 - [Usage Limitations](/tidb-limitations.md)
 

basic-features.md

@@ -0,0 +1,80 @@
+---
+title: TiDB Basic Features
+summary: Learn about the basic features of TiDB.
+category: introduction
+---
+
+# TiDB Basic Features
+
+This document introduces the basic features of TiDB.
+
+## Data types
+
+- Numeric types: `BIT`, `BOOL|BOOLEAN`, `SMALLINT`, `MEDIUMINT`, `INT|INTEGER`, `BIGINT`, `FLOAT`, `DOUBLE`, `DECIMAL`.
+
+- Date and time types: `DATE`, `TIME`, `DATETIME`, `TIMESTAMP`, `YEAR`.
+
+- String types: `CHAR`, `VARCHAR`, `TEXT`, `TINYTEXT`, `MEDIUMTEXT`, `LONGTEXT`, `BINARY`, `VARBINARY`, `BLOB`, `TINYBLOB`, `MEDIUMBLOB`, `LONGBLOB`, `ENUM`, `SET`.
+
+- The `JSON` type.
+
+## Operators
+
+- Arithmetic operators, bit operators, comparison operators, logical operators, date and time operators, and so on.
+
+## Character sets and collations
+
+- Character sets: `UTF8`, `UTF8MB4`, `BINARY`, `ASCII`, `LATIN1`.
+
+- Collations: `UTF8MB4_GENERAL_CI`, `UTF8MB4_GENERAL_BIN`, `UTF8_GENERAL_CI`, `UTF8_GENERAL_BIN`, `BINARY`.
+
+## Functions
+
+- Control flow functions, string functions, date and time functions, bit functions, data type conversion functions, data encryption and decryption functions, compression and decompression functions, information functions, JSON functions, aggregation functions, window functions, and so on.
+
+## SQL statements
+
+- Fully supports standard Data Definition Language (DDL) statements, such as `CREATE`, `DROP`, `ALTER`, `RENAME`, `TRUNCATE`, and so on.
+
+- Fully supports standard Data Manipulation Language (DML) statements, such as `INSERT`, `REPLACE`, `SELECT`, subqueries, `UPDATE`, `LOAD DATA`, and so on.
+
+- Fully supports standard transactional and locking statements, such as `START TRANSACTION`, `COMMIT`, `ROLLBACK`, `SET TRANSACTION`, and so on.
+
+- Fully supports standard database administration statements, such as `SHOW`, `SET`, and so on.
+
+- Fully supports standard utility statements, such as `DESCRIBE`, `EXPLAIN`, `USE`, and so on.
+
+- Fully supports the `GROUP BY` and `ORDER BY` clauses.
+
+- Fully supports the standard `LEFT OUTER JOIN` and `RIGHT OUTER JOIN` SQL statements.
+
+- Fully supports the standard SQL table and column aliases.
+
+## Partitioning
+
+- Supports Range partitioning
+- Supports Hash partitioning
+
+## Views
+
+- Supports general views
+
+## Constraints
+
+- Supports non-empty constraints
+- Supports primary key constraints
+- Supports unique constraints
+
+## Security
+
+- Supports privilege management based on RBAC (role-based access control)
+- Supports password management
+- Supports communication and data encryption
+- Supports IP allowlist
+- Supports audit
+
+## Tools
+
+- Supports fast backup
+- Supports data migration from MySQL to TiDB using tools
+- Supports deploying and maintaining TiDB using tools

mysql-compatibility.md

@@ -205,4 +205,4 @@ The following column types are supported by MySQL, but **NOT** by TiDB:
 + FLOAT4/FLOAT8
 + FIXED (alias for DECIMAL)
 + SERIAL (alias for BIGINT UNSIGNED NOT NULL AUTO_INCREMENT UNIQUE)
-+ SQL_TSI_* (including SQL_TSI_YEAR, SQL_TSI_MONTH, SQL_TSI_WEEK, SQL_TSI_DAY, SQL_TSI_HOUR, SQL_TSI_MINUTE and SQL_TSI_SECOND)
++ `SQL_TSI_*` (including SQL_TSI_YEAR, SQL_TSI_MONTH, SQL_TSI_WEEK, SQL_TSI_DAY, SQL_TSI_HOUR, SQL_TSI_MINUTE and SQL_TSI_SECOND)