Specification: | DB2 CLI 2.1 |
SQLGetPosition() is used to return the starting position of one string within a LOB value (the source). The source value must be a LOB locator, the search string can be a LOB locator or a literal string.
The source and search LOB locators can be any that have been returned from the database from a fetch or a SQLGetSubString() call during the current transaction.
Syntax
SQLRETURN SQLGetPosition (SQLHSTMT StatementHandle, /* hstmt */ SQLSMALLINT LocatorCType, SQLINTEGER SourceLocator, SQLINTEGER SearchLocator, SQLCHAR FAR *SearchLiteral, SQLINTEGER SearchLiteralLength, SQLUINTEGER FromPosition, SQLUINTEGER FAR *LocatedAt, SQLINTEGER FAR *IndicatorValue);
Function Arguments
Table 115. SQLGetPosition Arguments
Data Type | Argument | Use | Description | ||
---|---|---|---|---|---|
SQLHSTMT | StatementHandle | input | Statement handle. This can be any statement handle which has been allocated but which does not currently have a prepared statement assigned to it. | ||
SQLSMALLINT | LocatorCType | input | The C type of the source LOB locator. This may be:
| ||
SQLINTEGER | Locator | input | Locator must be set to the source LOB locator. | ||
SQLINTEGER | SearchLocator | input | If the SearchLiteral pointer is NULL and if SearchLiteralLength is set to 0, then SearchLocator must be set to the LOB locator associated with the search string; otherwise, this argument is ignored. | ||
SQLCHAR * | SearchLiteral | input | This argument points to the area of storage that contains the search
string literal.
If SearchLiteralLength is 0, this pointer must be NULL. | ||
SQLINTEGER | SearchLiteralLength | input | The length of the string in SearchLiteral(in bytes).
a
If this argument value is 0, then the argument SearchLocator is meaningful. | ||
SQLUINTEGER | FromPosition | input | For BLOBs and CLOBs, this is the position of the first byte within the source string at which the search is to start. to be returned by the function. For DBCLOBs, this is the first character. The start byte or character is numbered 1. | ||
SQLUINTEGER * | LocatedAt | output | For BLOBs and CLOBs, this is the byte position at which the string was
located or, if not located, the value zero. For DBCLOBs, this is the
character position.
If the length of the source string is zero, the value 1 is returned. | ||
SQLINTEGER * | IndicatorValue | output | Always set to zero. | ||
|
Usage
SQLGetPosition() is used in conjunction with SQLGetSubString() in order to obtain any portion of a string in a random manner. In order to use SQLGetSubString(), the location of the substring within the overall string must be known in advance. In situations where the start of that substring can be found by a search string, SQLGetPosition() can be used to obtain the starting position of that substring.
The Locator and SearchLocator (if used) arguments can contain any valid LOB locator which has not been explicitly freed using a FREE LOCATOR statement or implicitly freed because the transaction during which it was created has terminated.
The Locator and SearchLocator must have the same LOB locator type.
The statement handle must not have been associated with any prepared statements or catalog function calls.
Return Codes
Diagnostics
Table 116. SQLGetPosition SQLSTATEs
SQLSTATE | Description | Explanation |
---|---|---|
07006 | Invalid conversion. | The combination of LocatorCType and either of the LOB locator values is not valid. |
40003 08S01 | Communication link failure. | The communication link between the application and data source failed before the function completed. |
42818 | The operands of an operator or function are not compatible. | The length of the pattern is longer than 4000 bytes. |
58004 | Unexpected system failure. | Unrecoverable system error. |
HY001 | Memory allocation failure. | DB2 CLI is unable to allocate memory required to support execution or completion of the function. |
HY009 | Invalid argument value. | The pointer to the LocatedAt argument was NULL.
The argument value for FromPosition was not greater than 0.
LocatorCType is not one of SQL_C_CLOB_LOCATOR, SQL_C_BLOB_LOCATOR, or SQL_C_DBCLOB_LOCATOR. |
HY010 | Function sequence error. | The specified StatementHandle is not in an allocated
state.
The function was called while in a data-at-execute (SQLParamData(), SQLPutData()) operation. The function was called while within a BEGIN COMPOUND and END COMPOUND SQL operation. An asynchronously executing function (not this one) was called for the StatementHandle and was still executing when this function was called. |
HY013 | Unexpected memory handling error. | DB2 CLI was unable to access memory required to support execution or completion of the function. |
HY090 | Invalid string or buffer length. | The value of SearchLiteralLength was less than 1, and not SQL_NTS. |
HYC00 | Driver not capable. | The application is currently connected to a data source that does not support large objects. |
0F001 | The LOB token variable does not currently represent any value. | The value specified for Locator or SearchLocator is not currently a LOB locator. |
Restrictions
This function is not available when connected to a DB2 server that does not support Large Objects. Call SQLGetFunctions() with the function type set to SQL_API_SQLGETPOSITION and check the fExists output argument to determine if the function is supported for the current connection.
(The complete sample dtlob.c is also available here .)
/* From the CLI sample dtlob.c */ /* ... */ /* get the starting postion of the CLOB piece of data */ sqlrc = SQLGetPosition( hstmtLocUse, SQL_C_CLOB_LOCATOR, clobLoc, 0, ( SQLCHAR * ) "Interests", strlen( "Interests"), 1, &clobPiecePos, &ind ) ;
References