xcall SQL, SQLOP_GET_INFO, cmdhdr, infostring
This operation may be used to request various bits of information from the database server.
Parameters
cmdhdr (ST_SQL_CMDHDR), [in/out]
The fields of interest to this opcode in the cmdhdr structure (defined in SQL.DEF) are listed below.
Field |
Dir |
Notes |
|---|---|---|
handle |
in |
handle to connection (returned from SQLOP_INIT_CONN) |
dbmsconid |
in |
|
opflags |
in |
specifies the information requested (see SQLINFO_xxx in table below) |
cmdarg1,2 |
n/a |
|
rc |
out |
return code (0 = ok, see SQLERR_xxx) |
rcext |
out |
extended error code |
info1,2 |
out |
info requested may be returned here if it can be represented by an integer or double. |
sqlstate |
out |
ANSI standard SQL state code |
reshdl |
n/a |
|
psthdl |
in |
Set to value returned from last SQLOP_PST_PREPARE if last operation was on a prepared statement; else 0. |
opflags Symbol |
Value |
Notes |
|---|---|---|
SQLINFO_HOST |
1 |
Get host info (into infostring) |
SQLINFO_SERVER |
2 |
Get server version info (into both infostring and info1) |
SQLINFO_CLIENT |
3 |
Get client version info (into both infostring and info1) |
SQLINFO_QUERY |
4 |
(MySQL only) Returns details (into infostring) following these statements: INSERT INTO … SELECT INSERT INFO … VALUES(…),(…),… Format: Records: 1 Duplicates: 0 Warnings: 0 LOAD DATA INFILE Format: Records: 1 Deleted: 1 Skipped: 0 Warnings: 0 ALTER TABLE Format: Records: 50 Duplicates: 0 Warnings 0 UPDATE Format: Rows matched: 40 Changed: 40 Warnings: 0 |
SQLINFO_FIELDCOUNT |
5 |
Returns (into info1) # fields in most recent query. Will be 0 for non-select queries (providing a way to determine whether the non-return of rows from last statement was normal. |
SQLINFO_ROWCOUNT |
6 |
Returns (into info2) # rows in result set. (not always available - see notes below.) |
SQLINFO_CONID |
7 |
Returns connector ID (name, e.g. “LIBASHMYSQL”) in infostring |
SQLINFO_CONVER |
8 |
Returns connector version into info1 as an integer coded as MmmEEEp where M=major version, mm=minor version, EEE=edit number, and p=patch number. For example, 1023456 would indicate 1.2.345.6. Also returns the version in the #.#.###.# format into the infostring parameter. |
SQLINFO_CONDESCR |
9 |
Returns into infostring a description of the connector (e.g. “MySQL 5.1 (native)”) |
SQLINFO_AFFECTEDROWS |
10 |
When called immediately after a query that updates the database (such as update, delete, or insert), returns (into info2) the number of rows affected by the operation. |
SQLINFO_AUTOINCID |
11 |
When called immediately after an INSERT or UPDATE on a column using AUTO_INCREMENT field, returns the value of the AUTO_INCREMENT expression. |
infostring [string, out]
String information relating to the request may be returned here, if applicable.
Notes
Depending on the database, driver and other attributes, the number of rows selected in a query may not be available, such as when the query result set is held on the server and the client has a dynamic or sensitive cursor into the set, meaning that the size of the set can change between the time the query was submitted and all the rows fetched. In such a case, SQLINFO_ROWCOUNT will set info2 to 0 (MySQL connector) or -1 (ODBC connector).
