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SQLTables Function

Conformance
Version Introduced: ODBC 1.0 Standards Compliance: Open Group

Summary
SQLTables returns the list of table, catalog, or schema names, and table types, stored in a specific data source. The driver returns the information as a result set.

Syntax

  
SQLRETURN SQLTables(  
     SQLHSTMT       StatementHandle,  
     SQLCHAR *      CatalogName,  
     SQLSMALLINT    NameLength1,  
     SQLCHAR *      SchemaName,  
     SQLSMALLINT    NameLength2,  
     SQLCHAR *      TableName,  
     SQLSMALLINT    NameLength3,  
     SQLCHAR *      TableType,  
     SQLSMALLINT    NameLength4);  

Arguments

StatementHandle
[Input] Statement handle for retrieved results.

CatalogName
[Input] Catalog name. The CatalogName argument accepts search patterns if the SQL_ODBC_VERSION environment attribute is SQL_OV_ODBC3; it does not accept search patterns if SQL_OV_ODBC2 is set. If a driver supports catalogs for some tables but not for others, such as when a driver retrieves data from different DBMSs, an empty string ("") indicates those tables that do not have catalogs.

If the SQL_ATTR_METADATA_ID statement attribute is set to SQL_TRUE, CatalogName is treated as an identifier and its case is not significant. If it is SQL_FALSE, CatalogName is a pattern value argument; it is treated literally, and its case is significant. For more information, see Arguments in Catalog Functions.

NameLength1
[Input] Length in characters of *CatalogName.

SchemaName
[Input] String search pattern for schema names. 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 ("") indicates those tables that do not have schemas.

If the SQL_ATTR_METADATA_ID statement attribute is set to SQL_TRUE, SchemaName is treated as an identifier and its case is not significant. If it is SQL_FALSE, SchemaName is a pattern value argument; it is treated literally, and its case is significant.

NameLength2
[Input] Length in characters of *SchemaName.

TableName
[Input] String search pattern for table names.

If the SQL_ATTR_METADATA_ID statement attribute is set to SQL_TRUE, TableName is treated as an identifier and its case is not significant. If it is SQL_FALSE, TableName is a pattern value argument; it is treated literally, and its case is significant.

NameLength3
[Input] Length in characters of *TableName.

TableType
[Input] List of table types to match.

Notice that the SQL_ATTR_METADATA_ID statement attribute has no effect upon the TableType argument. TableType is a value list argument, regardless of the setting of SQL_ATTR_METADATA_ID.

NameLength4
[Input] Length in characters of *TableType.

Returns

SQL_SUCCESS, SQL_SUCCESS_WITH_INFO, SQL_STILL_EXECUTING, SQL_ERROR, or SQL_INVALID_HANDLE.

Diagnostics

When SQLTables returns SQL_ERROR or SQL_SUCCESS_WITH_INFO, an associated SQLSTATE value can be obtained by calling SQLGetDiagRec with a HandleType of SQL_HANDLE_STMT and a Handle of StatementHandle. The following table lists the SQLSTATE values typically returned by SQLTables and explains each one in the context of this function; the notation "(DM)" precedes the descriptions of SQLSTATEs returned by the Driver Manager. The return code associated with each SQLSTATE value is SQL_ERROR, unless noted otherwise.

SQLSTATE Error Description
01000 General warning Driver-specific informational message. (Function returns SQL_SUCCESS_WITH_INFO.)
08S01 Communication link failure The communication link between the driver and the data source to which the driver was connected failed before the function completed processing.
24000 Invalid cursor state A cursor was open on the StatementHandle, and SQLFetch or SQLFetchScroll had been called. This error is returned by the Driver Manager if SQLFetch or SQLFetchScroll has not returned SQL_NO_DATA and is returned by the driver if SQLFetch or SQLFetchScroll has returned SQL_NO_DATA.

A cursor was open on the StatementHandle, but SQLFetch or SQLFetchScroll had not been called.
40001 Serialization failure The transaction was rolled back because of a resource deadlock with another transaction.
40003 Statement completion unknown The associated connection failed during the execution of this function, and the state of the transaction cannot be determined.
HY000 General error An error occurred for which there was no specific SQLSTATE and for which no implementation-specific SQLSTATE was defined. The error message returned by SQLGetDiagRec in the *MessageText buffer describes the error and its cause.
HY001 Memory allocation error The driver was unable to allocate memory that is required to support execution or completion of the function.
HY008 Operation canceled Asynchronous processing was enabled for the StatementHandle. The function was called, and before it completed execution, SQLCancel or SQLCancelHandle was called on the StatementHandle. Then the function was called again on the StatementHandle.

The function was called, and before it completed execution, SQLCancel or SQLCancelHandle was called on the StatementHandle from a different thread in a multithread application.
HY009 Invalid use of null pointer The SQL_ATTR_METADATA_ID statement attribute was set to SQL_TRUE, the CatalogName argument was a null pointer, and the SQL_CATALOG_NAME InfoType returns that catalog names are supported.

(DM) The SQL_ATTR_METADATA_ID statement attribute was set to SQL_TRUE, and the SchemaName or TableName argument was a null pointer.
HY010 Function sequence error (DM) An asynchronously executing function was called for the connection handle that is associated with the StatementHandle. This asynchronous function was still executing when SQLTables was called.

(DM) SQLExecute, SQLExecDirect, or SQLMoreResults was called for the StatementHandle and returned SQL_PARAM_DATA_AVAILABLE. This function was called before data was retrieved for all streamed parameters.

(DM) An asynchronously executing function (not this one) was called for the StatementHandle and was still executing when this function was called.

(DM) SQLExecute, SQLExecDirect, SQLBulkOperations, or SQLSetPos was called for the StatementHandle and returned SQL_NEED_DATA. This function was called before data was sent for all data-at-execution parameters or columns.
HY013 Memory management error The function call could not be processed because the underlying memory objects could not be accessed, possibly because of low memory conditions.
HY090 Invalid string or buffer length (DM) The value of one of the length arguments was less than 0 but not equal to SQL_NTS.

The value of one of the name length arguments exceeded the maximum length value for the corresponding name.
HY117 Connection is suspended due to unknown transaction state. Only disconnect and read-only functions are allowed. (DM) For more information about suspended state, see SQLEndTran Function.
HYC00 Optional feature not implemented A catalog was specified, and the driver or data source does not support catalogs.

A schema was specified, and the driver or data source does not support schemas.

A string search pattern was specified for the catalog name, table schema, or table name, and the data source does not support search patterns for one or more of those arguments.

The combination of the current settings of the SQL_ATTR_CONCURRENCY and SQL_ATTR_CURSOR_TYPE statement attributes was not supported by the driver or data source.

The SQL_ATTR_USE_BOOKMARKS statement attribute was set to SQL_UB_VARIABLE, and the SQL_ATTR_CURSOR_TYPE statement attribute was set to a cursor type for which the driver does not support bookmarks.
HYT00 Timeout expired The query timeout period expired before the data source returned the requested result set. The timeout period is set through SQLSetStmtAttr, SQL_ATTR_QUERY_TIMEOUT.
HYT01 Connection timeout expired The connection timeout period expired before the data source responded to the request. The connection timeout period is set through SQLSetConnectAttr, SQL_ATTR_CONNECTION_TIMEOUT.
IM001 Driver does not support this function (DM) The driver associated with the StatementHandle does not support the function.
IM017 Polling is disabled in asynchronous notification mode Whenever the notification model is used, polling is disabled.
IM018 SQLCompleteAsync has not been called to complete the previous asynchronous operation on this handle. If the previous function call on the handle returns SQL_STILL_EXECUTING and if notification mode is enabled, SQLCompleteAsync must be called on the handle to do post-processing and complete the operation.

Comments

SQLTables lists all tables in the requested range. A user may or may not have SELECT privileges to any of these tables. To check accessibility, an application can:

  • Call SQLGetInfo and check the SQL_ACCESSIBLE_TABLES information type.

  • Call SQLTablePrivileges to check the privileges for each table.

Otherwise, the application must be able to handle a situation where the user selects a table for which SELECT privileges are not granted.

The SchemaName and TableName arguments accept search patterns. The CatalogName argument accepts search patterns if the SQL_ODBC_VERSION environment attribute is SQL_OV_ODBC3; it does not accept search patterns if SQL_OV_ODBC2 is set. If SQL_OV_ODBC3 is set, an ODBC 3*.x* driver will require that wildcard characters in the CatalogName argument be escaped to be treated literally. For more information about valid search patterns, see Pattern Value Arguments.

Note

For more information about the general use, arguments, and returned data of ODBC catalog functions, see Catalog Functions.

To support enumeration of catalogs, schemas, and table types, the following special semantics are defined for the CatalogName, SchemaName, TableName, and TableType arguments of SQLTables:

  • If CatalogName is SQL_ALL_CATALOGS and SchemaName and TableName are empty strings, the result set contains a list of valid catalogs for the data source. (All columns except the TABLE_CAT column contain NULLs.)

  • If SchemaName is SQL_ALL_SCHEMAS and CatalogName and TableName are empty strings, the result set contains a list of valid schemas for the data source. (All columns except the TABLE_SCHEM column contain NULLs.)

  • If TableType is SQL_ALL_TABLE_TYPES and CatalogName, SchemaName, and TableName are empty strings, the result set contains a list of valid table types for the data source. (All columns except the TABLE_TYPE column contain NULLs.)

If TableType is not an empty string, it must contain a list of comma-separated values for the types of interest; each value can be enclosed in single quotation marks (') or unquoted, for example, 'TABLE', 'VIEW' or TABLE, VIEW. An application should always specify the table type in uppercase; the driver should convert the table type to whatever case is needed by the data source. If the data source does not support a specified table type, SQLTables does not return any results for that type.

SQLTables returns the results as a standard result set, ordered by TABLE_TYPE, TABLE_CAT, TABLE_SCHEM, and TABLE_NAME. For information about how this information might be used, see Uses of Catalog Data.

To determine the actual lengths of the TABLE_CAT, TABLE_SCHEM, and TABLE_NAME columns, an application can call SQLGetInfo with the SQL_MAX_CATALOG_NAME_LEN, SQL_MAX_SCHEMA_NAME_LEN, and SQL_MAX_TABLE_NAME_LEN information types.

The following columns have been renamed for ODBC 3*.x*. The column name changes do not affect backward compatibility because applications bind by column number.

ODBC 2.0 column ODBC 3*.x* column
TABLE_QUALIFIER TABLE_CAT
TABLE_OWNER TABLE_SCHEM

The following table lists the columns in the result set. Additional columns beyond column 5 (REMARKS) can be defined by the driver. An application should gain access to driver-specific columns by counting down from the end of the result set instead of specifying an explicit ordinal position. For more information, see Data Returned by Catalog Functions.

Column name Column number Data type Comments
TABLE_CAT (ODBC 1.0) 1 Varchar Catalog name; NULL if not applicable to the data source. If a driver supports catalogs for some tables but not for others, such as when the driver retrieves data from different DBMSs, it returns an empty string ("") for those tables that do not have catalogs.
TABLE_SCHEM (ODBC 1.0) 2 Varchar Schema name; NULL if not applicable to the data source. If a driver supports schemas for some tables but not for others, such as when the driver retrieves data from different DBMSs, it returns an empty string ("") for those tables that do not have schemas.
TABLE_NAME (ODBC 1.0) 3 Varchar Table name.
TABLE_TYPE (ODBC 1.0) 4 Varchar Table type name; one of the following: "TABLE", "VIEW", "SYSTEM TABLE", "GLOBAL TEMPORARY", "LOCAL TEMPORARY", "ALIAS", "SYNONYM", or a data source-specific type name.

The meanings of "ALIAS" and "SYNONYM" are driver-specific.
REMARKS (ODBC 1.0) 5 Varchar A description of the table.

Example

The following sample code does not free handles and connections. See SQLFreeHandle Function and SQLFreeStmt Function for code samples to free handles and statements.

// SQLTables.cpp  
// compile with: user32.lib odbc32.lib  
#include <windows.h>  
#include <sqlext.h>  
#include <strsafe.h>  
  
// simple helper functions  
int MySQLSuccess(SQLRETURN rc) {  
   return (rc == SQL_SUCCESS || rc == SQL_SUCCESS_WITH_INFO);  
}  
  
struct DataBinding {  
   SQLSMALLINT TargetType;  
   SQLPOINTER TargetValuePtr;  
   SQLINTEGER BufferLength;  
   SQLLEN StrLen_or_Ind;  
};  
  
void printCatalog(const struct DataBinding* catalogResult) {  
   if (catalogResult[0].StrLen_or_Ind != SQL_NULL_DATA)   
      printf("Catalog Name = %s\n", (char *)catalogResult[0].TargetValuePtr);  
}  
  
// remember to disconnect and free memory, and free statements and handles  
int main() {  
   int bufferSize = 1024, i, numCols = 5;  
   struct DataBinding* catalogResult = (struct DataBinding*) malloc( numCols * sizeof(struct DataBinding) );  
   wchar_t* dbName = (wchar_t *)malloc( sizeof(wchar_t)*bufferSize );  
   wchar_t* userName = (wchar_t *)malloc( sizeof(wchar_t)*bufferSize );  
  
   // declare and initialize the environment, connection, statement handles  
   SQLHENV henv = NULL;   // Environment     
   SQLHDBC hdbc = NULL;   // Connection handle  
   SQLHSTMT hstmt = NULL;   // Statement handle  
  
   SQLRETURN retCode;  
   HWND desktopHandle = GetDesktopWindow();   // desktop's window handle  
   SQLWCHAR connStrbuffer[1024];  
   SQLSMALLINT connStrBufferLen;  
  
   retCode = SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &henv);  
   retCode = SQLSetEnvAttr(henv, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, -1);  
   retCode = SQLAllocHandle(SQL_HANDLE_DBC, henv, &hdbc);  
   retCode = SQLSetConnectAttr(hdbc, SQL_LOGIN_TIMEOUT, (SQLPOINTER)10, 0);  
   retCode = SQLDriverConnect(hdbc, desktopHandle, (SQLCHAR*)"Driver={SQL Server}", SQL_NTS, (SQLCHAR*)connStrbuffer, 1024 + 1, &connStrBufferLen, SQL_DRIVER_PROMPT);  
   retCode = SQLAllocHandle(SQL_HANDLE_STMT, hdbc, &hstmt);  
   retCode = SQLGetInfo(hdbc, SQL_DATABASE_NAME, dbName, (SQLSMALLINT)bufferSize, (SQLSMALLINT *)&bufferSize);  
   retCode = SQLGetInfo(hdbc, SQL_USER_NAME, userName, (SQLSMALLINT)bufferSize, (SQLSMALLINT *)&bufferSize);  
  
   bufferSize = 1024;  
  
   // allocate memory for the binding  
   // free this memory when done  
   for ( i = 0 ; i < numCols ; i++ ) {  
      catalogResult[i].TargetType = SQL_C_CHAR;  
      catalogResult[i].BufferLength = (bufferSize + 1);  
      catalogResult[i].TargetValuePtr = malloc( sizeof(unsigned char)*catalogResult[i].BufferLength );  
   }  
  
   // setup the binding (can be used even if the statement is closed by closeStatementHandle)  
   for ( i = 0 ; i < numCols ; i++ )  
      retCode = SQLBindCol(hstmt, (SQLUSMALLINT)i + 1, catalogResult[i].TargetType, catalogResult[i].TargetValuePtr, catalogResult[i].BufferLength, &(catalogResult[i].StrLen_or_Ind));  
  
   // all catalogs query  
   printf( "A list of names of all catalogs\n" );  
   retCode = SQLTables( hstmt, (SQLCHAR*)SQL_ALL_CATALOGS, SQL_NTS, (SQLCHAR*)"", SQL_NTS, (SQLCHAR*)"", SQL_NTS, (SQLCHAR*)"", SQL_NTS );  
   for ( retCode = SQLFetch(hstmt) ;  MySQLSuccess(retCode) ; retCode = SQLFetch(hstmt) )  
      printCatalog( catalogResult );  
}  
For information about See
Binding a buffer to a column in a result set SQLBindCol Function
Canceling statement processing SQLCancel Function
Returning privileges for a column or columns SQLColumnPrivileges Function
Returning the columns in a table or tables SQLColumns Function
Fetching a single row or a block of data in a forward-only direction SQLFetch Function
Fetching a block of data or scrolling through a result set SQLFetchScroll Function
Returning table statistics and indexes SQLStatistics Function
Returning privileges for a table or tables SQLTablePrivileges Function

See Also

ODBC API Reference
ODBC Header Files