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MgQfValueMgQfValue — Represents a single value (or a parameter) |
MgQfValue; guint mg_qf_value_get_type (void); GObject* mg_qf_value_new (MgQuery *query, MgServerDataType *type); void mg_qf_value_set_value (MgQfValue *field, const GdaValue *val); const GdaValue* mg_qf_value_get_value (MgQfValue *field); void mg_qf_value_set_default_value (MgQfValue *field, const GdaValue *default_val); const GdaValue* mg_qf_value_get_default_value (MgQfValue *field); GdaValueType mg_qf_value_get_value_type (MgQfValue *field); MgServerDataType* mg_qf_value_get_server_data_type (MgQfValue *field); void mg_qf_value_set_is_parameter (MgQfValue *field, gboolean is_param); gboolean mg_qf_value_is_parameter (MgQfValue *field); void mg_qf_value_set_not_null (MgQfValue *field, gboolean not_null); gboolean mg_qf_value_get_not_null (MgQfValue *field); gboolean mg_qf_value_is_value_null (MgQfValue *field, MgContext *context);
"handler-plugin" gchararray : Read / Write "query" gpointer : Read / Write "value-provider" gpointer : Read / Write "value-provider-xml-id" gchararray : Read / Write
The value held in this object can be of any type (a MgServerDataType object must be provided when creating the object). If the value can be considered as a parameter, then the possible values for this parameter can be limited by the result of the execution of a sub query (use the "value_provider*" properties to tell from which query field the values will be taken).
GObject* mg_qf_value_new (MgQuery *query, MgServerDataType *type);
Creates a new MgQfValue object which represents a value or a parameter.
query : | a MgQuery in which the new object will be |
type : | the requested type for the value |
Returns : | the new object |
void mg_qf_value_set_value (MgQfValue *field, const GdaValue *val);
Sets the value of field
, or removes it (if val
is NULL
)
field : | a MgQfValue object |
val : | the value to be set, or NULL
|
const GdaValue* mg_qf_value_get_value (MgQfValue *field);
Get the value stored by field
. If there is no value, but a default value exists, then the
default value is returned.n it's up to the caller to test if there is a default value for field
.
The default value can be of a different type than the one expected by field
.
field : | a MgQfValue object |
Returns : | the value or NULL |
void mg_qf_value_set_default_value (MgQfValue *field, const GdaValue *default_val);
Sets the default value of field
, or removes it (if default_val
is NULL
)
field : | a MgQfValue object |
default_val : | the default value to be set, or NULL
|
const GdaValue* mg_qf_value_get_default_value (MgQfValue *field);
Get the default value stored by field
.
field : | a MgQfValue object |
Returns : | the value or NULL |
GdaValueType mg_qf_value_get_value_type (MgQfValue *field);
Get the GDA type of value stored within field
field : | a MgQfValue object |
Returns : | the type |
MgServerDataType* mg_qf_value_get_server_data_type (MgQfValue *field);
Get the MgserverDataType type of field
field : | a MgQfValue object |
Returns : | the MgserverDataType type |
void mg_qf_value_set_is_parameter (MgQfValue *field, gboolean is_param);
Sets wether field
can be considered as a parameter
field : | a MgQfValue object |
is_param : |
gboolean mg_qf_value_is_parameter (MgQfValue *field);
Tells if field
can be considered as a parameter
field : | a MgQfValue object |
Returns : | TRUE if field can be considered as a parameter
|
void mg_qf_value_set_not_null (MgQfValue *field, gboolean not_null);
Sets if a NULL value is acceptable for field
. If not_null
is TRUE, then field
can't have a NULL value.
field : | a MgQfValue object |
not_null : |
gboolean mg_qf_value_get_not_null (MgQfValue *field);
Tells if field
can receive a NULL value.
field : | a MgQfValue object |
Returns : | TRUE if field can't have a NULL value
|
value-provider-xml-id
" property"value-provider-xml-id" gchararray : Read / Write
Default value: NULL
<< MgQfFunc | MgJoin >> |