The Structure of Metadata Datasets
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For each type of metadata you can access using TSQLDataSet, there is a predefined set of columns (fields) that are populated with information about the items of the requested type.
Contents
Information about tables
When you request information about tables (stTables or stSysTables), the resulting dataset includes a record for each table. It has the following columns:
Columns in tables of metadata listing tables :
| Column name | Field type | Contents |
|---|---|---|
|
RECNO |
ftInteger |
A record number that uniquely identifies each record. |
|
CATALOG_NAME |
ftString |
The name of the catalog (database) that contains the table. This is the same as the Database parameter on an SQL connection component. |
|
SCHEMA_NAME |
ftString |
The name of the schema that identifies the owner of the table. |
|
TABLE_NAME |
ftString |
The name of the table. This field determines the sort order of the dataset. |
|
TABLE_TYPE |
ftInteger |
Identifies the type of table. It is a sum of one or more of the following values: 1: Table 2: View 4: System table 8: Synonym 16: Temporary table 32: Local table. |
Information about stored procedures
When you request information about stored procedures (stProcedures), the resulting dataset includes a record for each stored procedure. It has following columns:
Columns in tables of metadata listing stored procedures :
| Column name | Field type | Contents |
|---|---|---|
|
RECNO |
ftInteger |
A record number that uniquely identifies each record. |
|
CATALOG_NAME |
ftString |
The name of the catalog (database) that contains the stored procedure. This is the same as the Database parameter on an SQL connection component. |
|
SCHEMA_NAME |
ftString |
The name of the schema that identifies the owner of the stored procedure. |
|
PROC_NAME |
ftString |
The name of the stored procedure. This field determines the sort order of the dataset. |
|
PROC_TYPE |
ftInteger |
Identifies the type of stored procedure. It is a sum of one or more of the following values: 1: Procedure 2: Function 4: Package 8: System procedure |
|
IN_PARAMS |
ftSmallint |
The number of input parameters |
|
OUT_PARAMS |
ftSmallint |
The number of output parameters. |
Information about fields
When you request information about the fields in a specified table (stColumns), the resulting dataset includes a record for each field. It includes the following columns:
Columns in tables of metadata listing fields :
| Column name | Field type | Contents |
|---|---|---|
|
RECNO |
ftInteger |
A record number that uniquely identifies each record. |
|
CATALOG_NAME |
ftString |
The name of the catalog (database) that contains the table whose fields you listing. This is the same as the Database parameter on an SQL connection component. |
|
SCHEMA_NAME |
ftString |
The name of the schema that identifies the owner of the field. |
|
TABLE_NAME |
ftString |
The name of the table that contains the fields. |
|
COLUMN_NAME |
ftString |
The name of the field. This value determines the sort order of the dataset. |
|
COLUMN_POSITION |
ftSmallint |
The position of the column in its table. |
|
COLUMN_TYPE |
ftInteger |
Identifies the type of value in the field. It is a sum of one or more of the following: 1: Row ID 2: Row Version 4: Auto increment field 8: Field with a default value |
|
COLUMN_DATATYPE |
ftSmallint |
The datatype of the column. This is one of the logical field type constants defined in sqllinks.pas. |
|
COLUMN_TYPENAME |
ftString |
A string describing the datatype. This is the same information as contained in COLUMN_DATATYPE and COLUMN_SUBTYPE, but in a form used in some DDL statements. |
|
COLUMN_SUBTYPE |
ftSmallint |
A subtype for the column's datatype. This is one of the logical subtype constants defined in sqllinks.pas. |
|
COLUMN_PRECISION |
ftInteger |
The size of the field type (number of characters in a string, bytes in a bytes field, significant digits in a BCD value, members of an ADT field, and so on). |
|
COLUMN_SCALE |
ftSmallint |
The number of digits to the right of the decimal on BCD values, or descendants on ADT and array fields. |
|
COLUMN_LENGTH |
ftInteger |
The number of bytes required to store field values. |
|
COLUMN_NULLABLE |
ftSmallint |
A Boolean that indicates whether the field can be left blank (0 means the field requires a value). |
Information about indexes
When you request information about the indexes on a table (stIndexes), the resulting dataset includes a record for each field in each record. (Multi-record indexes are described using multiple records) The dataset has the following columns:
Columns in tables of metadata listing indexes :
| Column name | Field type | Contents |
|---|---|---|
|
RECNO |
ftInteger |
A record number that uniquely identifies each record. |
|
CATALOG_NAME |
ftString |
The name of the catalog (database) that contains the index. This is the same as the Database parameter on an SQL connection component. |
|
SCHEMA_NAME |
ftString |
The name of the schema that identifies the owner of the index. |
|
TABLE_NAME |
ftString |
The name of the table for which the index is defined. |
|
INDEX_NAME |
ftString |
The name of the index. This field determines the sort order of the dataset. |
|
PKEY_NAME |
ftString |
Indicates the name of the primary key. |
|
COLUMN_NAME |
ftString |
The name of the field (column) in the index. |
|
COLUMN_POSITION |
ftSmallint |
The position of this field in the index. |
|
INDEX_TYPE |
ftSmallint |
Identifies the type of index. It is a sum of one or more of the following values: 1: Non-unique 2: Unique 4: Primary key |
|
SORT_ORDER |
ftString |
Indicates that the index is ascending (a) or descending (d). |
|
FILTER |
ftString |
Describes a filter condition that limits the indexed records. |
Information about stored procedure parameters
When you request information about the parameters of a stored procedure (stProcedureParams), the resulting dataset includes a record for each parameter. It has the following columns:
Columns in tables of metadata listing parameters :
| Column name | Field type | Contents |
|---|---|---|
|
RECNO |
ftInteger |
A record number that uniquely identifies each record. |
|
CATALOG_NAME |
ftString |
The name of the catalog (database) that contains the stored procedure. This is the same as the Database parameter on an SQL connection component. |
|
SCHEMA_NAME |
ftString |
The name of the schema that identifies the owner of the stored procedure. |
|
PROC_NAME |
ftString |
The name of the stored procedure that contains the parameter. |
|
PARAM_NAME |
ftString |
The name of the parameter. This field determines the sort order of the dataset. |
|
PARAM_TYPE |
ftSmallint |
Identifies the type of parameter. This is the same as a TParam object's ParamType property. |
|
PARAM_DATATYPE |
ftSmallint |
The datatype of the parameter. This is one of the logical field type constants defined in sqllinks.pas. |
|
PARAM_SUBTYPE |
ftSmallint |
A subtype for the parameter's datatype. This is one of the logical subtype constants defined in sqllinks.pas. |
|
PARAM_TYPENAME |
ftString |
A string describing the datatype. This is the same information as contained in PARAM_DATATYPE and PARAM_SUBTYPE, but in a form used in some DDL statements. |
|
PARAM_PRECISION |
ftInteger |
The maximum number of digits in floating-point values or bytes (for strings and Bytes fields). |
|
PARAM_SCALE |
ftSmallint |
The number of digits to the right of the decimal on floating-point values. |
|
PARAM_LENGTH |
ftInteger |
The number of bytes required to store parameter values. |
|
PARAM_NULLABLE |
ftSmallint |
A Boolean that indicates whether the parameter can be left blank (0 means the parameter requires a value). |
Information about Oracle packages
Columns in tables of metadata listing stored procedures :
| Column Name | Field type | Contents |
|---|---|---|
|
RECNO |
ftInteger |
A record number that uniquely identifies each record. |
|
CATALOG_NAME |
ftString |
The name of the catalog (database) that contains the package. This is the same as the Database parameter on an SQL connection component. |
|
SCHEMA_NAME |
ftString |
The name of the schema that identifies the owner of the package. |
|
OBJECT_NAME |
ftString |
The name of the package. This field determines the sort order of the dataset. |