Function SQLPrimaryKeysW 

pub unsafe extern "system" fn SQLPrimaryKeysW(
    hstmt: HStmt,
    catalog_name: *const WChar,
    catalog_name_length: i16,
    schema_name: *const WChar,
    schema_name_length: i16,
    table_name: *const WChar,
    table_name_length: i16,
) -> SqlReturn

Create a result set which contains the column names that make up the primary key for the table.

Parameters

• hstmt: Statement Handle
• catalog_name: Catalog name. If a driver supports catalogs for some tables but not for others, such as when the driver retrieves data from different DBMSs, an empty string (“”) denotes those tables that do not have catalogs. catalog_name cannot contain a string search pattern.
• catalog_name_length: Length of catalog_name in characters.
• schema_name: Schema name. If a driver supports schemas for some tables but not for others, such as when the driver retrieves data from different DBMSs, an empty string (“”) denotes those tables that do not have schemas. schema_name cannot contain a string search pattern.
• schema_name_length: Length of schema_name in characters.
• table_name: Table name. This argument can not be a null pointer. table_name cannot contain a string search pattern.

If StatementAttribute::MetadataId statement attribute is set to true, catalog, schema and table name parameters are treated as an identifiers and their case is not significant. If it is false, they are ordinary arguments. As such they treated literally and their case is significant.

See: https://learn.microsoft.com/sql/odbc/reference/syntax/sqlprimarykeys-function

Returns

SUCCESS, SUCCESS_WITH_INFO, STILL_EXECUTING, ERROR, or INVALID_HANDLE.