---json
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---
====== Postgres - How-to Connection ======



===== About =====
A [[docs:connection:howtos|default howto postgres connection]] and [[docs:service:howtos|howto service]] are provided after a fresh installation that is used in the [[howto:howto|howto's]].

To use this connection, you need to start the service (ie a [[#docker|docker image]])



===== Docker =====

==== Download and run the image ====

This connection is based on the [[https://hub.docker.com/_/postgres|Official Postgres Docker image]].

  * You can download and start the image with the following command:
<tabs enclosed-tabs>
<panel selected>
   <label>Tabul Service</label>
With [[:docs:tabul:service:start_command|tabul service start]]
<code bash>
tabul service start postgres
</code>
</panel>   
<panel>
   <label>Bash Docker</label>

  * [[docs:common:bash|Bash]]
<code bash>
docker run \
    -e POSTGRES_PASSWORD=welcome \
    -p 5432:5432 \
    -d \
    --name postgres \
    postgres:13.21
</code>
</panel>
<panel>
   <label>CMD / Powershell Docker</label>
  * [[docs:common:shell|CMD/Powershell]]
<code bash>
docker run ^
    -e POSTGRES_PASSWORD=welcome ^
    -p 5432:5432 ^
    -d ^
    --name postgres ^
    postgres:13.21
</code>
</panel>
</tabs>
\\

  * [[docs:tabul:connection:ping|Ping]] your connection to check that the database is up.
<unit>
<code bash>
tabul connection ping postgres
</code>
<console>
The connection (postgres) has been pinged successfully
</console>
</unit>


==== Start / Stop ====
You can then start and stop the image with the following command:

<code bash>
docker stop postgres
docker start postgres
</code>

===== Info =====

<unit>
<code bash>
tabul connection info postgres
</code>
<console>
Information about the connection (postgres)
Attribute                    Value                                       Description
--------------------------   -----------------------------------------   --------------------------------------------------------------------
BOOLEAN_DATA_TYPE            Native                                      Boolean data type used to store boolean values
BUILDER_CACHE_ENABLED        true                                        Enable or disable the builder cache
CHAR_DEFAULT_PRECISION       1                                           Default CHAR precision
COMMENT                      The howto postgres connection               A connection description
DATABASE_MAJOR_VERSION                                                   The major version number of the database
DATABASE_MINOR_VERSION                                                   The minor version number of the database
DATABASE_PRODUCT_NAME                                                    The name of the database
DATABASE_PRODUCT_VERSION                                                 The version of the database
DATE_DATA_TYPE               NATIVE                                      Date data type used to store date values
DRIVER                       org.postgresql.Driver                       The jdbc driver class
DRIVER_NAME                                                              The driver name
DRIVER_VERSION                                                           The driver version
HOST                                                                     Host Server
JDBC_MAJOR_VERSION                                                       The major version number of JDBC
JDBC_MINOR_VERSION                                                       The minor version number of JDBC
LOGIN_STATEMENTS                                                         Statements that runs after a connection has been established
MAX_CONCURRENT_THREAD                                                    The maximum number of threads that can be created against the system
MAX_NAME_IN_PATH                                                         The maximum number of names in a path
NAME                         postgres                                    The name of the connection
NAME_QUOTING_DISABLED_CASE   UPPERCASE                                   The case to apply when quoting is disabled
NAME_QUOTING_ENABLED         true                                        Enable quoting of names
NATIVES                                                                  Native Driver attributes (jdbc properties, ...)
NCHAR_DEFAULT_PRECISION      1                                           Default NCHAR precision
NVARCHAR_DEFAULT_PRECISION   0                                           Default NVARCHAR precision
ORIGIN                       CONF                                        The origin of the connection
PASSWORD                     welcome                                     The user password
PORT                         5432                                        Host Port
SUPPORT_BATCH_UPDATES                                                    If the system supports batch SQL updates
SUPPORT_NAMED_PARAMETERS                                                 If the system supports named parameters in the SQL statement
TIMESTAMP_DATA_TYPE          NATIVE                                      Timestamp data type used to store timestamp values
TIME_DATA_TYPE               NATIVE                                      Time format data type to store time values
URI                          jdbc:postgresql://localhost:5432/postgres   The uri of the connection
USER                         postgres                                    The user name
VARCHAR_DEFAULT_PRECISION    0                                           Default VARCHAR precision
WORKING_PATH                 public.                                     The working path (Schema for database, directory for file system)
</console>
</unit>

===== Support =====

==== Docker WSL2: Connection to localhost:5432 refused ====

If you get this message using Docker WSL2 on windows:
```
Connection to localhost:5432 refused
Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
```
You can try get the IP of the wsl machine
```bash
ip -br a
```
and use it in place of localhost. Example:
```bash
tabul connection upsert --uri "jdbc:postgresql://172.31.112.26:5432/postgres" postgres
```

Other user have reported that the following steps may help:
  * Settings another docker network space in `Docker > Settings > Docker Engine configuration`:
```json
{
  "bip": "192.168.200.1/24",
}
```
  * restart your computer