SQLGetInfo - Get general information

 

SQLGetInfo() returns general information (including supported data conversions) about the Database Management System (DBMS) that the application is currently connected to.

 

Syntax

SQLRETURN SQLGetInfo (SQLHDBC        hdbc,
                      SQLSMALLINT    fInfoType,
                      SQLPOINTER     rgbInfoValue,
                      SQLSMALLINT    cbInfoValueMax,
                      SQLSMALLINT    *pcbInfoValue);

 

Function arguments

Table 1. SQLGetInfo arguments
Data type Argument Use Description
SQLHDBC hdbc Input Database connection handle.
SQLSMALLINT fInfoType Input

Type of the required information.

SQLPOINTER rgbInfoValue Output (also input)

Pointer to buffer where this function stores the required information. Depending on the type of information being retrieved, four types of information can be returned:

  • 16-bit integer value

  • 32-bit integer value

  • 32-bit binary value

  • Null-terminated character string
SQLSMALLINT cbInfoValueMax Input The maximum length of the buffer pointed by rgbInfoValue pointer.
SQLSMALLINT * pcbInfoValue Output

Pointer to location where this function returns the total number of bytes available to return the required information.

If the value in the location pointed to by pcbInfoValue is greater than the size of the rgbInfoValue buffer as specified in cbInfoValueMax, then the string output information is truncated to cbInfoValueMax - 1 bytes and the function returns with SQL_SUCCESS_WITH_INFO.

 

Usage

Table 2 lists the possible values of fInfoType and a description of the information that SQLGetInfo() returns for that value.

Table 2. Information returned by SQLGetInfo
fInfoType Format Description and notes
SQL_ACTIVE_CONNECTIONS Short int The maximum number of active connections supported per application.

Zero is returned, indicating that the limit is dependent on system resources.

SQL_ACTIVE_STATEMENTS Short int The maximum number of active statements per connection.

Zero is returned, indicating that the limit is dependent on system resources.

SQL_AGGREGATE_FUNCTIONS 32-bit mask

A bit mask enumerating support for aggregation functions:

  • SQL_AF_ALL

  • SQL_AF_AVG

  • SQL_AF_COUNT

  • SQL_AF_DISTINCT

  • SQL_AF_MAX

  • SQL_AF_MIN

  • SQL_AF_SUM
SQL_CATALOG_NAME String A character string of Y indicates that the data source supports catalog names. N indicates that catalog names are not supported.
SQL_COLUMN_ALIAS String Whether the connection supports column aliases. The value Y is returned if the connection supports the concept of a column alias.
SQL_CONNECTION_JOB_NAME String When in server mode, this is a character string that contains the complete job name associated with the connection. When not in server mode, a function sequence error is returned.

SQL_CONVERT_BIGINT
SQL_CONVERT_BINARY
SQL_CONVERT_BLOB
SQL_CONVERT_CHAR
SQL_CONVERT_CLOB
SQL_CONVERT_DATE
SQL_CONVERT_DBCLOB
SQL_CONVERT_DECIMAL
SQL_CONVERT_DOUBLE
SQL_CONVERT_FLOAT
SQL_CONVERT_INTEGER
SQL_CONVERT_LONGVARBINARY
SQL_CONVERT_LONGVARCHAR
SQL_CONVERT_NUMERIC
SQL_CONVERT_REAL
SQL_CONVERT_SMALLINT
SQL_CONVERT_TIME
SQL_CONVERT_TIMESTAMP
SQL_CONVERT_VARBINARY
SQL_CONVERT_VARCHAR
SQL_CONVERT_WCHAR
SQL_CONVERT_WLONGVARCHAR
SQL_CONVERT_WVARCHAR

32-bit mask

This indicates the conversions supported by the data source with the CONVERT scalar function for data of the type named in the infoType. If the bit mask equals zero, the data source does not support any conversions for the data of the named type, including conversions to the same data type.

For example, to find out if a data source supports the conversion of SQL_INTEGER data to the SQL_DECIMAL data type, an application calls SQLGetInfo() with finfoType of SQL_CONVERT_INTEGER. The application then ANDs the returned bit mask with SQL_CVT_DECIMAL. If the resulting value is nonzero, then the conversion is supported. The following bit masks are used to determine which conversions are supported:

  • SQL_CONVERT_BLOB

  • SQL_CONVERT_CLOB

  • SQL_CONVERT_DBCLOB

  • SQL_CONVERT_SMALLINT

  • SQL_CONVERT_TIME

  • SQL_CONVERT_TIMESTAMP

  • SQL_CONVERT_VARBINARY

  • SQL_CONVERT_VARCHAR

  • SQL_CONVERT_WCHAR

  • SQL_CONVERT_WLONGVARCHAR

  • SQL_CONVERT_WVARCHAR

  • SQL_CVT_BIGINT

  • SQL_CVT_BINARY

  • SQL_CVT_CHAR

  • SQL_CVT_DATE

  • SQL_CVT_DECIMAL

  • SQL_CVT_DOUBLE

  • SQL_CVT_FLOAT

  • SQL_CVT_INTEGER

  • SQL_CVT_LONGVARBINARY

  • SQL_CVT_LONGVARCHAR

  • SQL_CVT_NUMERIC

  • SQL_CVT_REAL
SQL_CONVERT_FUNCTIONS 32 bit mask

This indicates the scalar conversion functions supported by the driver and associated data source:

  • SQL_FN_CVT_CONVERT is used to determine which conversion functions are supported.

  • SQL_FN_CVT_CAST is used to determine which cast functions are supported.
SQL_CORRELATION_NAME Short int

This indicates the degree of correlation name support by the system:

  • SQL_CN_ANY – Correlation name is supported and can be any valid user-defined name.

  • SQL_CN_NONE – Correlation name is not supported.

  • SQL_CN_DIFFERENT – Correlation name is supported but it must be different from the name of the table that it represents.
SQL_CURSOR_COMMIT_BEHAVIOR 16-bit integer

This indicates how a COMMIT operation affects cursors:

  • SQL_CB_DELETE destroys cursors and drops access plans for dynamic SQL statements.

  • SQL_CB_CLOSE destroys cursors, but retains access plans for dynamic SQL statements (including nonquery statements).

  • SQL_CB_PRESERVE retains cursors and access plans for dynamic statements (including nonquery statements). Applications can continue to fetch data, or close the cursor and reprocess the query without preparing the statement again.

After the COMMIT operation, a FETCH must be issued to reposition the cursor before actions such as positioned updates or deletes can be taken.

SQL_CURSOR_ROLLBACK_BEHAVIOR 16-bit integer

This indicates how a ROLLBACK operation affects cursors:

  • SQL_CB_DELETE destroys cursors and drops access plans for dynamic SQL statements.

  • SQL_CB_CLOSE destroys cursors, but retains access plans for dynamic SQL statements (including nonquery statements)

  • SQL_CB_PRESERVE retains cursors and access plans for dynamic statements (including nonquery statements). Applications can continue to fetch data, or close the cursor and run the query again without preparing the statement again.

DB2® servers do not have the SQL_CB_PRESERVE property.

SQL_DATA_SOURCE_NAME String Name of the connected data source for the connection handle.
SQL_DATA_SOURCE_READ_ONLY String A character string of Y indicates that the database is set to READ ONLY mode; an N indicates that it is not set to READ ONLY mode.

SQL_DATABASE_NAME

String

Name of the current database in use. This string is the same as that returned by the SELECT CURRENT SERVER SQL statement.

SQL_DBMS_NAME String Name of the Database Management System (DBMS) product being accessed. For example:

  • QSQ for DB2 Universal Database™ for iSeries™

  • SQL for DB2 for Linux®, UNIX®, and Windows®

  • DSN for DB2 Universal Database for z/OS®
SQL_DBMS_VER String Version of the DBMS product accessed.
SQL_DEFAULT_TXN_ISOLATION 32-bit mask

The default transaction-isolation level supported. One of the following masks are returned:

  • SQL_TXN_READ_UNCOMMITTED – Changes are immediately perceived by all transactions (dirty read, non-repeatable read, and phantoms are possible).

    This is equivalent to UR level.

  • SQL_TXN_READ_COMMITTED – Row read by transaction 1 can be altered and committed by transaction 2 (non-repeatable read and phantoms are possible).

    This is equivalent to CS level.

  • SQL_TXN_REPEATABLE_READ – A transaction can add or remove rows matching the search condition or a pending transaction (repeatable read, but phantoms are possible).

    This is equivalent to RS level.

  • SQL_TXN_SERIALIZABLE – Data affected by pending transaction is not available to other transactions (repeatable read, phantoms are not possible).

    This is equivalent to RR level.

  • SQL_TXN_VERSIONING – Not applicable to IBM® DBMSs.

  • SQL_TXN_NOCOMMIT – Any changes are effectively committed at the end of a successful operation; no explicit commit or rollback operation is allowed.

    This is a DB2 isolation level.

In IBM terminology,

  • SQL_TXN_READ_UNCOMMITTED is uncommitted read.

  • SQL_TXN_READ_COMMITTED is cursor stability.

  • SQL_TXN_REPEATABLE_READ is read stability.

  • SQL_TXN_SERIALIZABLE is repeatable read.
SQL_DESCRIBE_PARAMETER String Y if parameters can be described; N if not.
SQL_DRIVER_NAME String File name of the driver used to access the data source.
SQL_DRIVER_ODBC_VER String The version number of ODBC that the driver supports. DB2 ODBC returns 2.1.
SQL_GROUP_BY 16-bit integer This indicates the degree of support for the GROUP BY clause by the data source:

  • SQL_GB_NO_RELATION means there is no relationship between the columns in the GROUP BY and in the SELECT list.

  • SQL_GB_NOT_SUPPORTED – GROUP BY is not supported.

  • SQL_GB_GROUP_BY_EQUALS_SELECT – GROUP BY must include all nonaggregated columns in the select list.

  • SQL_GB_GROUP_BY_CONTAINS_SELECT – GROUP BY clause must contain all nonaggregated columns in the SELECT list.
SQL_IDENTIFIER_CASE 16-bit integer

This indicates case sensitivity of object names (such as table-name).

  • SQL_IC_UPPER – Identifier names are stored in uppercase in the system catalog.

  • SQL_IC_LOWER – Identifier names are stored in lowercase in the system catalog.

  • SQL_IC_SENSITIVE – Identifier names are case sensitive, and are stored in mixed case in the system catalog.

  • SQL_IC_MIXED – Identifier names are not case sensitive, and are stored in mixed case in the system catalog.

Identifier names in IBM DBMSs are not case sensitive.

SQL_IDENTIFIER_QUOTE_CHAR String Character used as the delimiter of a quoted string.
SQL_KEYWORDS String A character string containing a comma-separated list of all data source-specific keywords. This is a list of all reserved keywords. Interoperable applications should not use these keywords in object names. This list does not contain keywords specific to ODBC or keywords used by both the data source and ODBC.
SQL_LIKE_ESCAPE_CLAUSE String A character string that indicates whether an escape character is supported for the metacharacters percent and underscore in a LIKE predicate.
SQL_MAX_CATALOG_NAME_LEN 16-bit integer The maximum length of a catalog qualifier name; first part of a three-part table name (in bytes).
SQL_MAX_COLUMN_NAME_LEN Short int The maximum length of a column name.
SQL_MAX_COLUMNS_IN_GROUP_BY Short int The maximum number of columns in a GROUP BY clause.
SQL_MAX_COLUMNS_IN_INDEX Short int The maximum number of columns in an SQL index.
SQL_MAX_COLUMNS_IN_ORDER_BY Short int Maximum number of columns in an ORDER BY clause.
SQL_MAX_COLUMNS_IN_SELECT Short int The maximum number of columns in a SELECT statement.
SQL_MAX_COLUMNS_IN_TABLE Short int The maximum number of columns in an SQL table.
SQL_MAX_CURSOR_NAME_LEN Short int The maximum length of a cursor name.
SQL_MAX_OWNER_NAME_LEN Short int The maximum length of an owner name.
SQL_MAX_ROW_SIZE 32–bit unsigned integer The maximum length in bytes that the data source supports in a single row of a base table. It is zero if there is no limit.
SQL_MAX_SCHEMA_NAME_LEN Int The maximum length of a schema name.
SQL_MAX_STATEMENT_LEN 32–bit unsigned integer This indicates the maximum length of an SQL statement string in bytes, including the number of white spaces in the statement.
SQL_MAX_TABLE_NAME Short int The maximum length of a table name.
SQL_MAX_TABLES_IN_SELECT Short int The maximum number of tables in a SELECT statement.
SQL_MULTIPLE_ACTIVE_TXN String The character string Y indicates that active transactions on multiple connections are allowed. N indicates that only one connection at a time can have an active transaction.
SQL_NON_NULLABLE_COLUMNS 16-bit integer This indicates whether non-nullable columns are supported:

  • SQL_NNC_NON_NULL – columns can be defined as NOT NULL.

  • SQL_NNC_NULL – columns cannot be defined as NOT NULL.
SQL_NUMERIC_FUNCTIONS 32-bit mask

The scalar numeric functions supported.

The following bit masks are used to determine which numeric functions are supported:

  • SQL_FN_NUM_ABS

  • SQL_FN_NUM_ACOS

  • SQL_FN_NUM_ASIN

  • SQL_FN_NUM_ATAN

  • SQL_FN_NUM_ATAN2

  • SQL_FN_NUM_CEILING

  • SQL_FN_NUM_COS

  • SQL_FN_NUM_COT

  • SQL_FN_NUM_DEGREES

  • SQL_FN_NUM_EXP

  • SQL_FN_NUM_FLOOR

  • SQL_FN_NUM_LOG

  • SQL_FN_NUM_LOG10

  • SQL_FN_NUM_MOD

  • SQL_FN_NUM_PI

  • SQL_FN_NUM_POWER

  • SQL_FN_NUM_RADIANS

  • SQL_FN_NUM_RAND

  • SQL_FN_NUM_ROUND

  • SQL_FN_NUM_SIGN

  • SQL_FN_NUM_SIN

  • SQL_FN_NUM_SQRT

  • SQL_FN_NUM_TAN

  • SQL_FN_NUM_TRUNCATE
SQL_ODBC_API_CONFORMANCE 16-bit integer The level of ODBC conformance:

  • SQL_OAC_NONE

  • SQL_OAC_LEVEL1

  • SQL_OAC_LEVEL2
SQL_ODBC_SQL_CONFORMANCE 16-bit integer A value of:

  • SQL_OSC_MINIMUM means minimum ODBC SQL grammar supported

  • SQL_OSC_CORE means core ODBC SQL grammar supported

  • SQL_OSC_EXTENDED means extended ODBC SQL grammar supported

For the definition of the previous types of ODBC SQL grammar, see Microsoft® ODBC 3.0 Software Development Kit and Programmer's Reference.

SQL_ORDER_BY_COLUMNS_IN_SELECT String Set to Y if columns in the ORDER BY clauses must be in the select list; otherwise set to N.
SQL_OUTER_JOINS String

The character string:

  • Y indicates that outer joins are supported, and DB2 ODBC supports the ODBC outer join request syntax.

  • N indicates that it is not supported.
SQL_OWNER_TERM or SQL_SCHEMA_TERM String The database vendor terminology for a schema (owner).
SQL_OWNER_USAGE or SQL_SCHEMA_USAGE 32-bit mask This indicates the type of SQL statements that have schema (owners) associated with them when these statements are processed. Schema qualifiers (owners) are as follows:

  • SQL_OU_DML_STATEMENTS is supported in all DML statements.

  • SQL_OU_PROCEDURE_INVOCATION is supported in the procedure invocation statement.

  • SQL_OU_TABLE_DEFINITION is supported in all table definition statements.

  • SQL_OU_INDEX_DEFINITION is supported in all index definition statements.

  • SQL_OU_PRIVILEGE_DEFINITION is supported in all privilege definition statements (that is, grant and revoke statements).
SQL_POSITIONED_STATEMENTS 32-bit mask

This indicates the degree of support for positioned UPDATE and positioned DELETE statements:

  • SQL_PS_POSITIONED_DELETE

  • SQL_PS_POSITIONED_UPDATE

  • SQL_PS_SELECT_FOR_UPDATE

    SQL_PS_SELECT_FOR_UPDATE indicates whether the data source requires the FOR UPDATE clause to be specified on a <query expression> for a column to be updated with the cursor.

SQL_PROCEDURE_TERM String Data source name for a procedure.
SQL_PROCEDURES String Whether the current server supports SQL procedures. The value Y is returned if the connection supports SQL procedures.
SQL_QUALIFIER_LOCATION or SQL_CATALOG_LOCATION 16-bit integer A 16-bit integer value indicated the position of the qualifier in a qualified table name. Zero indicates that qualified names are not supported.
SQL_QUALIFIER_NAME_SEPARATOR or SQL_CATALOG_NAME_SEPARATOR String The characters used as a separator between a catalog name and the qualified name element that follows it.
SQL_QUALIFIER_TERM or SQL_CATALOG_TERM String

The database vendor terminology for a qualifier.

This is the name that the vendor uses for the high-order part of a 3-part name.

Because DB2 ODBC does not support 3-part names, a zero-length string is returned.

For non-ODBC applications, the SQL_CATALOG_TERM symbolic name should be used instead of SQL_QUALIFIER_NAME.

SQL_QUALIFIER_USAGE or SQL_CATALOG_USAGE 32-bit mask This is similar to SQL_OWNER_USAGE except that this is used for catalog.
SQL_QUOTED_IDENTIFIER_CASE 16-bit integer

  • SQL_IC_UPPER – Quoted identifiers in SQL are case insensitive and stored in uppercase in the system catalog.

  • SQL_IC_LOWER – Quoted identifiers in SQL are case insensitive and are stored in lowercase in the system catalog.

  • SQL_IC_SENSITIVE – Quoted identifiers (delimited identifiers) in SQL are case sensitive and are stored in mixed case in the system catalog.

  • SQL_IC_MIXED – Quoted identifiers in SQL are case insensitive and are stored in mixed case in the system catalog.

This should be contrasted with the SQL_IDENTIFIER_CASE fInfoType, which is used to determine how (unquoted) identifiers are stored in the system catalog.

SQL_SEARCH_PATTERN_ESCAPE String Used to specify what the driver supports as an escape character for catalog functions, such as SQLTables() and SQLColumns().
SQL_SQL92_PREDICATES 32-bit mask

This indicates the predicates supported in a SELECT statement that SQL-92 defines.

  • SQL_SP_BETWEEN

  • SQL_SP_COMPARISON

  • SQL_SP_EXISTS

  • SQL_SP_IN

  • SQL_SP_ISNOTNULL

  • SQL_SP_ISNULL

  • SQL_SP_LIKE

  • SQL_SP_MATCH_FULL

  • SQL_SP_MATCH_PARTIAL

  • SQL_SP_MATCH_UNIQUE_FULL

  • SQL_SP_MATCH_UNIQUE_PARTIAL

  • SQL_SP_OVERLAPS

  • SQL_SP_QUANTIFIED_COMPARISON

  • SQL_SP_UNIQUE
SQL_SQL92_VALUE_EXPRESSIONS 32-bit mask

This indicates the value expressions supported that SQL-92 defines.

  • SQL_SVE_CASE

  • SQL_SVE_CAST

  • SQL_SVE_COALESCE

  • SQL_SVE_NULLIF
SQL_STRING_FUNCTIONS 32-bit bit mask This indicates which string functions are supported.

The following bit masks are used to determine which string functions are supported:

  • SQL_FN_STR_ASCII

  • SQL_FN_STR_CHAR

  • SQL_FN_STR_CONCAT

  • SQL_FN_STR_DIFFERENCE

  • SQL_FN_STR_INSERT

  • SQL_FN_STR_LCASE

  • SQL_FN_STR_LEFT

  • SQL_FN_STR_LENGTH

  • SQL_FN_STR_LOCATE

  • SQL_FN_STR_LOCATE_2

  • SQL_FN_STR_LTRIM

  • SQL_FN_STR_REPEAT

  • SQL_FN_STR_REPLACE

  • SQL_FN_STR_RIGHT

  • SQL_FN_STR_RTRIM

  • SQL_FN_STR_SOUNDEX

  • SQL_FN_STR_SPACE

  • SQL_FN_STR_SUBSTRING

  • SQL_FN_STR_UCASE

If an application can call the LOCATE scalar function with the string1, string2, and start arguments, the SQL_FN_STR_LOCATE bit mask is returned. If an application can only call the LOCATE scalar function with the string1 and string2, the SQL_FN_STR_LOCATE_2 bit mask is returned. If the LOCATE scalar function is fully supported, both bit masks are returned.

SQL_TIMEDATE_FUNCTIONS 32-bit mask

This indicates which time and date functions are supported.

The following bit masks are used to determine which date functions are supported:

  • SQL_FN_TD_CURDATE

  • SQL_FN_TD_CURTIME

  • SQL_FN_TD_DAYNAME

  • SQL_FN_TD_DAYOFMONTH

  • SQL_FN_TD_DAYOFWEEK

  • SQL_FN_TD_DAYOFYEAR

  • SQL_FN_TD_HOUR

  • SQL_FN_TD_JULIAN_DAY

  • SQL_FN_TD_MINUTE

  • SQL_FN_TD_MONTH

  • SQL_FN_TD_MONTHNAME

  • SQL_FN_TD_NOW

  • SQL_FN_TD_QUARTER

  • SQL_FN_TD_SECOND

  • SQL_FN_TD_SECONDS_SINCE_MIDNIGHT

  • SQL_FN_TD_TIMESTAMPADD

  • SQL_FN_TD_TIMESTAMPDIFF

  • SQL_FN_TD_WEEK

  • SQL_FN_TD_YEAR
SQL_TXN_CAPABLE Short int This indicates whether transactions can contain DDL or DML or both:

  • SQL_TC_NONE – Transactions are not supported.

  • SQL_TC_DML – Transactions can only contain DML statements (SELECT, INSERT, UPDATE, DELETE, and so on). DDL statements (CREATE TABLE, DROP INDEX, and so on) encountered in a transaction cause an error.

  • SQL_TC_DDL_COMMIT – Transactions can only contain DML statements. DDL statements encountered in a transaction cause the transaction to be committed.

  • SQL_TC_DDL_IGNORE – Transactions can only contain DML statements. DDL statements encountered in a transaction are ignored.

  • SQL_TC_ALL – Transactions can contain DDL and DML statements in any order.

SQL_USER_NAME

String

User name used in a particular database.

 

Return codes

 

Diagnostics

Table 3. SQLGetInfo SQLSTATEs
SQLSTATE Description Explanation
01004 Data truncated The requested information is returned as a null-terminated string and its length exceeded the length of the application buffer as specified in cbInfoValueMax. The argument pcbInfoValue contains the actual (not truncated) length of the requested information.
08003 Connection not open The type of information requested in fInfoType requires an open connection. Only SQL_ODBC_VER does not require an open connection.
40003 * Statement completion unknown The communication link between the CLI and the data source fails before the function completes processing.
58004 System error Unrecoverable system error.
HY001 Memory allocation failure The driver is unable to allocate memory required to support the processing or completion of the function.
HY009 Argument value that is not valid The argument rgbInfoValue is a null pointer

An fInfoType that is not valid is specified.

HY013 * Memory management problem The driver is unable to access memory required to support the processing or completion of the function.

 

Parent topic:

DB2 UDB CLI functions