trivial-pooled-database

2019-03-07

Trivial Pooled Database Manual

pipeline status Quicklisp

[in package TRIVIAL-POOLED-DATABASE]

Description

This library provides a multi-threaded DB connection pool.

Working Example

After loading the project one has to first initialize the connection pool by calling INITIALIZE-CONNECTION-POOL, passing it the access credentials and database information.

(let ((username "sql_user")
      (passwd "password")
      (schema "minerva")
      (host "localhost"))
  (trivial-pooled-database:initialize-connection-pool username passwd schema host))

Once the pool is initialized, a SQL command can be executed and all connection handling is hidden inside the pool.

(trivial-pooled-database:select "customers"
                '(:ID :NAME :ADDRESS :GOLD-MEMBER-P :LAST-VISIT)
                (format nil "`GOLD-MEMBER-P`= ~a" gold-member-status)
                :order-by "`NAME` DESC"
                :limit 1)

Installing trivial-pooled-database

This project is available in the latest QuickLisp distribution, so installing it is reduced to calling:

(ql:quickload :trivial-pooled-database)

Note: trivial-pooled-database depends on features from bordeaux-threads which are not yes available in QuickLisp.
Because of this, following step is necessary before loading trivial-pooled-database:

cd $HOME/quicklisp/local-projects
git clone https://github.com/sionescu/bordeaux-threads.git

Exported Symbols

  • [function] INITIALIZE-CONNECTION-POOL USER PWD SCHEMA HOST &KEY (INITIAL-POOL-SIZE 5) (MAX-POOL-SIZE 15) Initialize the connection pool by providing access credentials to the database and additionaly pool size information. USER - user name PWD - user password SCHEMA - database schema to use HOST - database host name or IP address INITIAL-POOL-SIZE - the number of connections to be created at initialization MAX-POOL-SIZE - Maximal number of connections allowed

  • [function] SHUTDOWN-CONNECTION-POOL Disconnects all database connections and shuts down the connection pool.

  • [function] SELECT TABLE FIELDS WHERE &KEY (LIMIT NIL) (ORDER-BY NIL)

    Selects all entries from TABLE matching the WHERE clause returning the FIELDS (might be '*' to select all fields of the table).
    Optionally LIMIT indicates the maximum number of entries to return and ORDER-BY defines the ordering of the result.

  • [function] SELECT TABLE FIELDS WHERE &KEY (LIMIT NIL) (ORDER-BY NIL)

    Selects all entries from TABLE matching the WHERE clause returning the FIELDS (might be '*' to select all fields of the table).
    Optionally LIMIT indicates the maximum number of entries to return and ORDER-BY defines the ordering of the result.

  • [function] INSERT TABLE FIELDS VALUES

    Inserts a new entry into the database TABLE assigning each element in VALUES to its corresponding FIELD.

  • [function] UPDATE TABLE FIELDS VALUES WHERE

    Updates an entry of the table TABLE matching the WHERE clause. Each element in VALUES is assigned to its corresponding FIELD.

  • [function] EXECUTE-FUNCTION FN-NAME &REST PARAMETERS

    Executes a DB stored function identified by FN-NAME with the given PARAMETERS (if any) and returns it's value.

  • [function] EXECUTE CMD

    Allows for execution of a freely defined SQL command CMD.

License Information

This library is released under the MIT License. Please refer to the LICENSE to get the full licensing text.

Contributing to this project

Please refer to the CONTRIBUTING document for more information.