Enum odbc_sys::Desc

#[repr(u16)]pub enum Desc {
    Count,
    Type,
    Length,
    OctetLengthPtr,
    Precision,
    Scale,
    DatetimeIntervalCode,
    Nullable,
    IndicatorPtr,
    DataPtr,
    Name,
    Unnamed,
    OctetLength,
    AllocType,
    ArraySize,
    ArrayStatusPtr,
    AutoUniqueValue,
    BaseColumnName,
    BaseTableName,
    BindOffsetPtr,
    BindType,
    CaseSensitive,
    CatalogName,
    ConciseType,
    DatetimeIntervalPrecision,
    DisplaySize,
    FixedPrecScale,
    Label,
    LiteralPrefix,
    LiteralSuffix,
    LocalTypeName,
    MaximumScale,
    MinimumScale,
    NumPrecRadix,
    ParameterType,
    RowsProcessedPtr,
    RowVer,
    SchemaName,
    Searchable,
    TypeName,
    TableName,
    Unsigned,
    Updatable,
}

Used in SQLColAttributeW.

Variants

Count

SQL_DESC_COUNT. Returned in NumericAttributePtr. The number of columns available in the result set. This returns 0 if there are no columns in the result set. The value in the column_number argument is ignored.

Type

SQL_DESC_TYPE. Retruned in NumericAttributePtr. A numeric value that specifies the SQL data type. When ColumnNumber is equal to 0, SQL_BINARY is returned for variable-length bookmarks and SQL_INTEGER is returned for fixed-length bookmarks. For the datetime and interval data types, this field returns the verbose data type: SQL_DATETIME or SQL_INTERVAL. Note: To work against ODBC 2.x drivers, use SQL_DESC_CONCISE_TYPE instead.

Length

SQL_DESC_LENGTH. Returned in NumericAttributePtr. A numeric value that is either the maximum or actual character length of a character string or binary data type. It is the maximum character length for a fixed-length data type, or the actual character length for a variable-length data type. Its value always excludes the null-termination byte that ends the character string.

OctetLengthPtr

SQL_DESC_OCTET_LENGTH_PTR.

Precision

SQL_DESC_PRECISION. Returned in NumericAttributePtr. A numeric value that for a numeric data type denotes the applicable precision. For data types SQL_TYPE_TIME, SQL_TYPE_TIMESTAMP, and all the interval data types that represent a time interval, its value is the applicable precision of the fractional seconds component.

Scale

SQL_DESC_SCALE. Returned in NumericAttributePtr. A numeric value that is the applicable scale for a numeric data type. For DECIMAL and NUMERIC data types, this is the defined scale. It is undefined for all other data types.

DatetimeIntervalCode

SQL_DESC_DATETIME_INTERVAL_CODE.

Nullable

SQL_DESC_NULLABLE. Returned in NumericAttributePtr. SQL_ NULLABLE if the column can have NULL values; SQL_NO_NULLS if the column does not have NULL values; or SQL_NULLABLE_UNKNOWN if it is not known whether the column accepts NULL values.

IndicatorPtr

SQL_DESC_INDICATOR_PTR

DataPtr

SQL_DESC_DATA_PTR.

Name

SQL_DESC_NAME. Returned in CharacterAttributePtr. The column alias, if it applies. If the column alias does not apply, the column name is returned. In either case, SQL_DESC_UNNAMED is set to SQL_NAMED. If there is no column name or a column alias, an empty string is returned and SQL_DESC_UNNAMED is set to SQL_UNNAMED.

Unnamed

SQL_DESC_UNNAMED. Returned in NumericAttributePtr. SQL_NAMED or SQL_UNNAMED. If the SQL_DESC_NAME field of the IRD contains a column alias or a column name, SQL_NAMED is returned. If there is no column name or column alias, SQL_UNNAMED is returned.

OctetLength

SQL_DESC_OCTET_LENGTH. Returned in NumericAttributePtr. The length, in bytes, of a character string or binary data type. For fixed-length character or binary types, this is the actual length in bytes. For variable-length character or binary types, this is the maximum length in bytes. This value does not include the null terminator.

AllocType

SQL_DESC_ALLOC_TYPE.

ArraySize

SQL_DESC_ARRAY_SIZE

ArrayStatusPtr

SQL_DESC_ARRAY_STATUS_PTR

AutoUniqueValue

SQL_DESC_AUTO_UNIQUE_VALUE. Returned in NumericAttributePtr. true if the column is an autoincrementing column. false if the column is not an autoincrementing column or is not numeric. This field is valid for numeric data type columns only. An application can insert values into a row containing an autoincrement column, but typically cannot update values in the column. When an insert is made into an autoincrement column, a unique value is inserted into the column at insert time. The increment is not defined, but is data source-specific. An application should not assume that an autoincrement column starts at any particular point or increments by any particular value.

BaseColumnName

SQL_DESC_BASE_COLUMN_NAME. Returned in CharacterAttributePtr. The base column name for the result set column. If a base column name does not exist (as in the case of columns that are expressions), then this variable contains an empty string.

BaseTableName

SQL_DESC_BASE_TABLE_NAME. Returned in CharacterAttributePtr. The name of the base table that contains the column. If the base table name cannot be defined or is not applicable, then this variable contains an empty string.

BindOffsetPtr

SQL_DESC_BIND_OFFSET_PTR.

BindType

SQL_DESC_BIND_TYPE.

CaseSensitive

SQL_DESC_CASE_SENSITIVE. Returned in NumericAttributePtr. true if the column is treated as case-sensitive for collations and comparisons. false if the column is not treated as case-sensitive for collations and comparisons or is noncharacter.

CatalogName

SQL_DESC_CATALOG_NAME. Returned in CharacterAttributePtr. The catalog of the table that contains the column. The returned value is implementation-defined if the column is an expression or if the column is part of a view. If the data source does not support catalogs or the catalog name cannot be determined, an empty string is returned. This VARCHAR record field is not limited to 128 characters.

ConciseType

SQL_DESC_CONCISE_TYPE. Returned in NumericAttributePtr. The concise data type. For the datetime and interval data types, this field returns the concise data type; for example, SQL_TYPE_TIME or SQL_INTERVAL_YEAR.

DatetimeIntervalPrecision

SQL_DESC_DATETIME_INTERVAL_PRECISION

DisplaySize

SQL_DESC_DISPLAY_SIZE. Returned in NumericAttributePtr. Maximum number of characters required to display data from the column.

FixedPrecScale

SQL_DESC_FIXED_PREC_SCALE. Returned in NumericAttributePtr. true if the column has a fixed precision and nonzero scale that are data source-specific. false if the column does not have a fixed precision and nonzero scale that are data source-specific.

Label

SQL_DESC_LABEL. Returned in CharacterAttributePtr. The column label or title. For example, a column named EmpName might be labeled Employee Name or might be labeled with an alias. If a column does not have a label, the column name is returned. If the column is unlabeled and unnamed, an empty string is returned.

LiteralPrefix

SQL_DESC_LITERAL_PREFIX. Returned in CharacterAttributePtr. This VARCHAR(128) record field contains the character or characters that the driver recognizes as a prefix for a literal of this data type. This field contains an empty string for a data type for which a literal prefix is not applicable.

LiteralSuffix

SQL_DESC_LITERAL_SUFFIX. Returned in CharacterAttributePtr. This VARCHAR(128) record field contains the character or characters that the driver recognizes as a suffix for a literal of this data type. This field contains an empty string for a data type for which a literal suffix is not applicable.

LocalTypeName

SQL_DESC_LOCAL_TYPE_NAME. Returned in CharacterAttributePtr. This VARCHAR(128) record field contains any localized (native language) name for the data type that may be different from the regular name of the data type. If there is no localized name, then an empty string is returned. This field is for display purposes only. The character set of the string is locale-dependent and is typically the default character set of the server.

MaximumScale

SQL_DESC_MAXIMUM_SCALE.

MinimumScale

SQL_DESC_MINIMUM_SCALE.

NumPrecRadix

SQL_DESC_NUM_PREC_RADIX. Returned in NumericAttributePtr. If the data type in the SQL_DESC_TYPE field is an approximate numeric data type, this SQLINTEGER field contains a value of 2 because the SQL_DESC_PRECISION field contains the number of bits. If the data type in the SQL_DESC_TYPE field is an exact numeric data type, this field contains a value of 10 because the SQL_DESC_PRECISION field contains the number of decimal digits. This field is set to 0 for all non-numeric data types.

ParameterType

SQL_DESC_PARAMETER_TYPE.

RowsProcessedPtr

SQL_DESC_ROWS_PROCESSED_PTR.

RowVer

SQL_DESC_ROWVER.

SchemaName

SQL_DESC_SCHEMA_NAME. Returned in CharacterAttributePtr. The schema of the table that contains the column. The returned value is implementation-defined if the column is an expression or if the column is part of a view. If the data source does not support schemas or the schema name cannot be determined, an empty string is returned. This VARCHAR record field is not limited to 128 characters.

Searchable

SQL_DESC_SEARCHABLE. Returned in NumericAttributePtr. SQL_PRED_NONE if the column cannot be used in a WHERE clause. SQL_PRED_CHAR if the column can be used in a WHERE clause but only with the LIKE predicate. SQL_PRED_BASIC if the column can be used in a WHERE clause with all the comparison operators except LIKE. SQL_PRED_SEARCHABLE if the column can be used in a WHERE clause with any comparison operator. Columns of type SQL_LONGVARCHAR and SQL_LONGVARBINARY usually return SQL_PRED_CHAR.

TypeName

SQL_DESC_TYPE_NAME. Returned in CharacterAttributePtr. Data source-dependent data type name; for example, “CHAR”, “VARCHAR”, “MONEY”, “LONG VARBINARY”, or “CHAR ( ) FOR BIT DATA”. If the type is unknown, an empty string is returned.

TableName

SQL_DESC_TABLE_NAME. Returned in CharacterAttributePtr. The name of the table that contains the column. The returned value is implementation-defined if the column is an expression or if the column is part of a view. If the table name can not be determined an empty string is returned.

Unsigned

SQL_DESC_UNSIGNED. Returned in NumericAttributePtr. true if the column is unsigned (or not numeric). false if the column is signed.

Updatable

SQL_DESC_UPDATABLE. Returned in NumericAttributePtr. Column is described by the values for the defined constants: SQL_ATTR_READONLY, SQL_ATTR_WRITE, SQL_ATTR_READWRITE_UNKNOWN. Updatable Describes the updatability of the column in the result set, not the column in the base table. The updatability of the base column on which the result set column is based may be different from the value in this field. Whether a column is updatable can be based on the data type, user privileges, and the definition of the result set itself. If it is unclear whether a column is updatable, SQL_ATTR_READWRITE_UNKNOWN should be returned.

Trait Implementations

impl Clone for Desc

fn clone(&self) -> Desc

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Desc

impl Debug for Desc

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Desc

impl PartialEq<Desc> for Desc

fn eq(&self, other: &Desc) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl StructuralEq for Desc

impl StructuralPartialEq for Desc