Release Notes
- v2.5
- v2.4
- v2.3
- v2.2
- v2.1
- v2.0
- v1.19

Introduction
Quick Start
Table Design
Data Loading
Data Export
Using StarRocks
Reference
- SQL Reference
- Function Reference
  - Date Functions
  - Geographic Functions
  - String Functions
  - Aggregation Functions
  - Bitmap Functions
  - Array Functions
  - cast function
  - hash function
  - Crytographic Functions
    - md5
    - sha2
  - Math Functions
    - RAND
    - square
  - Utility Functions
    - uuid
    - uuid_numeric
- System variables
- Error code
- System limits
Administration
- Build in Docker
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- Configuration
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- Backup and Restore
- Data Recovery
  - Data Recovery
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- Replica
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- Authentication
- Resource Management
FAQ
- Deployment
- Data Migration
  - Data Ingestion
  - Data Export
- SQL
- Others FAQs
Benchmark
- SSB Benchmark
- TPC-H Benchmark

Developers
- Contribute to StarRocks
- Code Style Guides
  - protobuf style guides
  - thrift style guides
- Use the debuginfo file for debugging
- Development Environment
- Trace Tools
  - Trace
Integration
- Integrate with StarRocks
- Authenticate to AWS resources

Edit

COUNT

description

Syntax

COUNT([DISTINCT] expr)

It is used to return the number of rows that satisfy the requirements.

example


MySQL > select count(*)
from log_statis
group by datetime;
+----------+
| count(*) |
+----------+
| 28515903 |
+----------+


MySQL > select count(datetime)
from log_statis
group by datetime;
+-------------------+
| count(`datetime`) |
+-------------------+
|         28521682  |
+-------------------+

MySQL > select count(distinct datetime)
from log_statis
group by datetime;
+----------------------------+
| count(DISTINCT `datetime`) |
+----------------------------+
|                    71045   |
+----------------------------+

keyword

COUNT

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In this article

COUNT