delete

Delete in the databases.

DELETE

NAME

delete - Delete in the databases.

SYNOPSIS

delete( [db:pointer,] tables:string, wantarray:true|false, count:integer, using:string,error:variable,delete_upload:true|false,delete_foreign:true|false, join:string, having:string, selectby:string, orderby:string, groupby:string, limit:string, args:string, uid:integer, page:integer, prefix:true|false, countperpage:integer);

DESCRIPTION

This function is used to delete elements in tables.

Since the database does not support page, limit, groupby having, join. A select is perform to get the list of uid and then a delete is perform on this list. As a consequence, the field uid must be present in the table.

Also, if delete_upload or delete_foreign is set to true (default), than a select is perform and the delete is done after.

In order to delete foreign element in table the following is perform:

If we want to delete uid 5 of table sn_test1:

Get the UID from sn_tables for sn_test1 =⇒ uid_table
If delete_foreign is true than
- For each foreign_table and foreign field from table sn_fields where field_type = foreign and uid_sn_tables = uid_table
  - For each element in foreign_table where foreign_field = 5;
    - Recusively delete uid foreign_table, element
If delete_upload is true than
- Select field_name from sn_fields where field_type = image and uid_sn_tables = uid_table
- Select * from table sn_test1 where uid = 5;
- Delete file if any

PARAMETERS

tables: Specify list of tables commads separated.

delete_upload: Delete uploaded file.

delete_foreign: Delete foreign elements.

using: Specify using keyword.

wantarray: By default rows are return as a context with the name of the column. If this parameter is true, it return only the value.

count: If parameter page is used, then the function must calculate the number of element. If you already have this number, you can use this parameter to initialize it.; join; Specify join statement for select.

having: Specify having statement for select.

selectby: Specify condition for the WHERE statement. See args \? is replase with ?.

noargs: By default ? in selectby are replace by values in args. If noargs is true, no replacement is done.

args: Specify arguments wihin selecby to quote and replace value. All ? are replace with one arguments.

orderby: Specify ORDER BY statement.

groupby: Specify GROUP BY statement.

limit: Specify LIMIT statement.

uid: Specify UID for the WHERE statement.

page: Specify page number based on count and countperpage.

prefix: Prefix name of field with table name followed by _.

countperpage: Number of elements in a page.

db: Specify alternate database pointer as return from connect function; Starting from version 5.6.2 if db is undefined, it will fall back to the default database of the project.

RETURN

This function return an has array with thw following elements:

sql: Build SQL statement.

nbcols: Number of columns in result.

offset: Offset calculated when page is specify. If not, the value is -1.

sqlerr: Error message if any.

count: Calculated count (or the one specify in parameter) if page is specify. -1 otherwise.

error: Specify if we got an error or not

sqlcode: SQL error code. 0 if no error.

nbrows: Number of rows in result

rows: List if rows. The rows can be an array of hash or an array of array if wantarray is true.

EXAMPLES

Note: In the followings examples, the _ between the { should be removed to make it work.

res={_{ delete(); }}. return .*tables must be specify.*
res={_{ delete(tables:"sn_test1"); }}. ALL records will be removed from table sn_test1
res={_{ a=delete(tables:"sn_test1",uid:1); a; }}. uid 1 will be removed from table sn_test1. return {"error":false,"sqlcode":0,"nbrows":0,"rows":[],"sql":"DELETE FROM sn_test1 WHERE sed_dev_test.uid = '1'","nbcols":0,"affrow":0,"offset":-1,"sqlerr":"","count":-1}

AUTHOR

Written by Pierre Laplante, <laplante@sednove.com>

MODIFICATIONS

1.0 2014-09-09 21:24:14 laplante@sednove.com

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