Nonstop Database, HiRDB Version 9 UAP Development Guide
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18.17.5 Estimating the ResultSet object size
The following shows the formulas for estimating the ResultSet object size.
- Formula (for 32-bit mode)
ResultSet object size =
16000 + (900 + locator access object length + receive buffer size)
x number of ResultSet instances + retrieval results accumulation area size x number of ResultSet instances 2
(bytes)
|
- Formula (for 64-bit mode)
ResultSet object size =
17000 + (1300 + locator access object length + receive buffer size)
x number of ResultSet instances + retrieval results accumulation area size x number of ResultSet instances 2
(bytes)
|
- Locator access object length: If the locator facility is used (LOCATOR specified in the url argument of DriverManager.getConnection or in the LONGVARBINARY_ACCESS user property, or LOCATOR specified by the setLONGVARBINARY_Access method of a DataSource interface), add 1,600.
- Receive buffer size: Use the following formula to determine the value:
MAX(32768,
(240 + data length of retrieved row x number of rows for block transfer) 4096 x 4096)
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- Data length of retrieved row: Use the following formula to determine the value:
- Definition length of column data: If the data is BLOB or BINARY and a locator is used, the value is 4. If a locator is not used, the value is one of the following:
- If HiRDB_for_Java_MAXBINARYSIZE is omitted:
8 + definition length
- If HiRDB_for_Java_MAXBINARYSIZE is specified:
MIN(8 + definition length, 8 + HiRDB_for_Java_MAXBINARYSIZE value)
- Number of rows for block transfer: If the block transfer facility is not used, the value is 1.
- Retrieval results accumulation area size: Use the following formula to determine the value:
- Real length of column data: See the following table:
Output data attribute |
Real length of column data |
INTEGER |
4 |
SMALLINT |
2 |
DECIMAL(m, n) |
m 2 + 1 |
FLOAT |
8 |
SMALLFLT |
4 |
BLOB or BINARY |
If the locator facility is used, the value is 4; if not, the value is one of the following:
- If HiRDB_for_Java_MAXBINARYSIZE is omitted:
8 + real length
- If HiRDB_for_Java_MAXBINARYSIZE is specified:
MIN(8 + real length, 8 + MAXBINARYSIZE value)
|
Other |
Real length |
- Number of ResultSet instances 2: Number of ResultSet instances whose result set type is ResultSet.TYPE_SCROLL_INSENSITIVE or ResultSet.TYPE_SCROLL_SENSITIVE
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