db2_statistics

Returns a result set listing the index and statistics for a table

Description

resource db2_statistics(
    resource $connection,
    stringnull $qualifier,
    stringnull $schema,
    string $table_name,
    bool $unique
)

Returns a result set listing the index and statistics for a table.

Parameters

connection

A valid connection to an IBM DB2, Cloudscape, or Apache Derby database.

qualifier

A qualifier for DB2 databases running on OS/390 or z/OS servers. For other databases, pass null or an empty string.

schema

The schema that contains the targeted table. If this parameter is null, the statistics and indexes are returned for the schema of the current user.

table_name

The name of the table.

unique

When unique is true, the information for all indexes in the table are returned. Otherwise, only the information for unique indexes in the table are returned.

Return Values

Returns a statement resource with a result set containing rows describing the statistics and indexes for the base tables matching the specified parameters. The rows are composed of the following columns:

Column name Description
TABLE_CAT The catalog that contains the table. The value is null if this table does not have catalogs.
TABLE_SCHEM Name of the schema that contains the table.
TABLE_NAME Name of the table.
NON_UNIQUE

An integer value representing whether the index prohibits unique values, or whether the row represents statistics on the table itself:

Return value Parameter type
0 (SQL_FALSE) The index allows duplicate values.
1 (SQL_TRUE) The index values must be unique.
null This row is statistics information for the table itself.

INDEX_QUALIFIER A string value representing the qualifier that would have to be prepended to INDEX_NAME to fully qualify the index.
INDEX_NAME A string representing the name of the index.
TYPE

An integer value representing the type of information contained in this row of the result set:

Return value Parameter type
0 (SQL_TABLE_STAT) The row contains statistics about the table itself.
1 (SQL_INDEX_CLUSTERED) The row contains information about a clustered index.
2 (SQL_INDEX_HASH) The row contains information about a hashed index.
3 (SQL_INDEX_OTHER) The row contains information about a type of index that is neither clustered nor hashed.

ORDINAL_POSITION The 1-indexed position of the column in the index. null if the row contains statistics information about the table itself.
COLUMN_NAME The name of the column in the index. null if the row contains statistics information about the table itself.
ASC_OR_DESC A if the column is sorted in ascending order, D if the column is sorted in descending order, null if the row contains statistics information about the table itself.
CARDINALITY

If the row contains information about an index, this column contains an integer value representing the number of unique values in the index.

If the row contains information about the table itself, this column contains an integer value representing the number of rows in the table.

PAGES

If the row contains information about an index, this column contains an integer value representing the number of pages used to store the index.

If the row contains information about the table itself, this column contains an integer value representing the number of pages used to store the table.

FILTER_CONDITION Always returns null.

See Also

  • db2_column_privileges
  • db2_columns
  • db2_foreign_keys
  • db2_primary_keys
  • db2_procedure_columns
  • db2_procedures
  • db2_special_columns
  • db2_table_privileges
  • db2_tables