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The Structure of Metadata Datasets

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.

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.  

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.  

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).  

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.  

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).  

 

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.  
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