sys.columns (Transact-SQL)
Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric
Returns a row for each column of an object that has columns, such as views or tables. The following list contains the object types that have columns:
- Table-valued assembly functions (FT)
- Inline table-valued SQL functions (IF)
- Internal tables (IT)
- System tables (S)
- Table-valued SQL functions (TF)
- User tables (U)
- Views (V)
Column name | Data type | Description |
---|---|---|
object_id |
int | ID of the object to which this column belongs. |
name |
sysname | Name of the column. Is unique within the object. |
column_id |
int | ID of the column. Is unique within the object. Column IDs might not be sequential. |
system_type_id |
tinyint | ID of the system type of the column. |
user_type_id |
int | ID of the type of the column as defined by the user. To return the name of the type, join to the sys.types catalog view on this column. |
max_length |
smallint | Maximum length (in bytes) of the column.-1 = Column data type is varchar(max), nvarchar(max), varbinary(max), or xml.For text, ntext, and image columns, the max_length value is 16 (representing the 16-byte pointer only) or the value set by sp_tableoption 'text in row' . |
precision |
tinyint | Precision of the column if numeric-based; otherwise, 0 . |
scale |
tinyint | Scale of column if numeric-based; otherwise, 0 . |
collation_name |
sysname | Name of the collation of the column if character-based; otherwise NULL . |
is_nullable |
bit | 1 = Column is nullable0 = Column isn't nullable |
is_ansi_padded |
bit | 1 = Column uses ANSI_PADDING ON behavior if character, binary, or variant0 = Column isn't character, binary, or variant |
is_rowguidcol |
bit | 1 = Column is a declared ROWGUIDCOL |
is_identity |
bit | 1 = Column has identity values |
is_computed |
bit | 1 = Column is a computed column |
is_filestream |
bit | 1 = Column is a FILESTREAM column |
is_replicated |
bit | 1 = Column is replicated |
is_non_sql_subscribed |
bit | 1 = Column has a non-SQL Server subscriber |
is_merge_published |
bit | 1 = Column is merge-published |
is_dts_replicated |
bit | 1 = Column is replicated by using SSIS |
is_xml_document |
bit | 1 = Content is a complete XML document0 = Content is a document fragment, or the column data type isn't xml |
xml_collection_id |
int | Nonzero if the data type of the column is xml and the XML is typed. The value is the ID of the collection containing the validating XML schema namespace of the column0 = No XML schema collection |
default_object_id |
int | ID of the default object, regardless of whether it's a stand-alone object sp_bindefault, or an inline, column-level DEFAULT constraint. The parent_object_id column of an inline column-level default object is a reference back to the table itself.0 = No default |
rule_object_id |
int | ID of the stand-alone rule bound to the column by using sys.sp_bindrule. 0 = No stand-alone rule. For column-level CHECK constraints, see sys.check_constraints. |
is_sparse |
bit | 1 = Column is a sparse column. For more information, see Use sparse columns. |
is_column_set |
bit | 1 = Column is a column set. For more information, see Use sparse columns. |
generated_always_type |
tinyint | Identifies when the column value is generated (is always 0 for columns in system tables).Applies to: SQL Server 2016 (13.x) and later versions, and SQL Database. 0 = NOT_APPLICABLE 1 = AS_ROW_START 2 = AS_ROW_END Applies to: SQL Server 2022 (16.x) and later versions, and SQL Database. 5 = AS_TRANSACTION_ID_START 6 = AS_TRANSACTION_ID_END 7 = AS_SEQUENCE_NUMBER_START 8 = AS_SEQUENCE_NUMBER_END For more information, see Temporal Tables (Relational databases). |
generated_always_type_desc |
nvarchar(60) | Textual description of the generated_always_type value (always NOT_APPLICABLE for columns in system tables)Applies to: SQL Server 2016 (13.x) and later versions, and SQL Database. NOT_APPLICABLE AS_ROW_START AS_ROW_END Applies to: SQL Server 2022 (16.x) and later versions, and SQL Database. AS_TRANSACTION_ID_START AS_TRANSACTION_ID_END AS_SEQUENCE_NUMBER_START AS_SEQUENCE_NUMBER_END |
encryption_type |
int | Encryption type:1 = Deterministic encryption2 = Randomized encryptionApplies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
encryption_type_desc |
nvarchar(64) | Encryption type description:RANDOMIZED DETERMINISTIC Applies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
encryption_algorithm_name |
sysname | Name of encryption algorithm. Only AEAD_AES_256_CBC_HMAC_SHA_512 is supported.Applies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
column_encryption_key_id |
int | ID of the column encryption key (CEK). Applies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
column_encryption_key_database_name |
sysname | The name of the database where the column encryption key exists if different than the database of the column. NULL if the key exists in the same database as the column.Applies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
is_hidden |
bit | Indicates if the column is hidden:0 = regular, not-hidden, visible column1 = hidden columnApplies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
is_masked |
bit | Indicates if the column is masked by dynamic data masking:0 = regular, not-masked column1 = column is maskedApplies to: SQL Server 2016 (13.x) and later versions, and SQL Database |
graph_type |
int | Internal column with a set of values. The values are between 1 and 8 for graph columns, and NULL for others. |
graph_type_desc |
nvarchar(60) | Identified for informational purposes only. Not supported. Future compatibility is not guaranteed. |
is_data_deletion_filter_column |
bit | Indicates if the column is the data retention filter column for the table. Applies to: Azure SQL Edge |
ledger_view_column_type |
int | If not NULL , indicates the type of a column in a ledger view:1 = TRANSACTION_ID 2 = SEQUENCE_NUMBER 3 = OPERATION_TYPE 4 = OPERATION_TYPE_DESC For more information, see Ledger overview. Applies to: SQL Server 2022 (16.x) and later versions, and SQL Database |
ledger_view_column_type_desc |
nvarchar(60) | If not NULL , contains a textual description of the the type of a column in a ledger view:TRANSACTION_ID SEQUENCE_NUMBER OPERATION_TYPE OPERATION_TYPE_DESC Applies to: SQL Server 2022 (16.x) and later versions, and SQL Database |
is_dropped_ledger_column |
bit | Indicates a ledger table column that was dropped. Applies to: SQL Server 2022 (16.x) and later versions, and SQL Database |
Permissions
The visibility of the metadata in catalog views is limited to securables that a user either owns, or on which the user was granted some permission. For more information, see Metadata Visibility Configuration.