CacheSize (Property)

ONLINE HELP
WINDEV, WEBDEV AND WINDEV MOBILE

Version:

Home | Sign in | English

This content has been translated automatically. Click here to view the French version.

Help / WLanguage / WLanguage properties / HFSQL properties

Equivalence
Retrieving the records
Managing the CacheSize property
hQueryWithoutCorrection constant

WINDEV

WEBDEV

WINDEV Mobile

Others

See also

HFSQL properties

CacheSize (Property)

In french: TailleCache

Available only with these kinds of connection

The CacheSize property is used to:

Get the maximum number of records that can be stored in the cache of the Native MySQL Connector.
Change the maximum number of records that can be stored in the cache of the Native MySQL Connector. In this case, when you open a file that uses an open connection, that connection will be closed and reopened with the new parameters.

Note: The connection can correspond:

a connection defined in the data model editor,
a connection defined with HConnect, HDescribeConnection or HOpenConnection.
a connection defined with a variable of type Connection.

Example

// Change the cache size of the Native MySQL Connector used by
// MyConnection
MyConnection.CacheSize = 450

Syntax

Getting the cache size for a connection Hide the details

<Cache size> = <Connection used>.CacheSize

<Cache size>: Integer

Cache size of the Native MySQL Connector.
If this parameter corresponds to:
-2: cache size is the default size (100 for MySQL Native Connector).
-1: cache size is unlimited.
0: cache stores no records. No record is retrieved.

<Connection used>: Character string or Connection variable

Name of the connection used. This name is defined:
in the data model editor,
with the HDescribeConnection and HOpenConnection functions,
with the Connection type.

Defining the cache size for a connection Hide the details

<Connection used>.CacheSize = <Cache size>

<Connection used>: Character string or Connection variable

Name of the connection used. This name is defined:
in the data model editor,
with the HDescribeConnection and HOpenConnection functions,
with the Connection type.

<Cache size>: Integer

New cache size of the Native MySQL Connector.
If this parameter corresponds to:
-2: cache size will be the default size (100 for MySQL Native Connector).
-1: cache size will be unlimited.
0: the cache will not store any records. No record will be retrieved.

Remarks

Equivalence

CtCacheSize is used to define the cache size for a MySQL connection. This property is kept for backward compatibility. It is recommended to use the CacheSize property.

Retrieving the records

The speed with which all records are retrieved is proportional to the size of the cache: the larger the cache, the faster the retrieval speed.

However, the smaller the cache size, the faster the first record will be read.

Warning: The memory occupied by the cache is proportional to the size of the cache.

Managing the CacheSize property

The CacheSize property is supported only by the Native MySQL Connector.

Other Native Connectors do not support the CacheSize property. In this case, the use of this property will be ignored and no error will be generated.

hQueryWithoutCorrection constant

If the query is executed without checking the SQL code (using the constant hRequêteSansCorrection): the size will be unlimited and cannot be modified thanks to the property CacheSize.