sesam_settransaction
Description
bool sesam_settransaction ( int isolation_level, int read_only)Returns: TRUE if the values are valid, and the settransaction() operation was successful, FALSE otherwise.
sesam_settransaction() overrides the default values for the "isolation level" and "read-only" transaction parameters (which are set in the SESAM configuration file), in order to optimize subsequent queries and guarantee database consistency. The overridden values are used for the next transaction only.
sesam_settransaction() can only be called before starting a transaction, not after the transaction has been started already.
To simplify the use in php scripts, the following constants have been predefined in php (see SESAM handbook for detailed explanation of the semantics):
Table 1. Valid values for "Isolation_Level" parameter
| Value | Constant | Meaning |
|---|---|---|
| 1 | SESAM_TXISOL_READ_UNCOMMITTED | Read Uncommitted |
| 2 | SESAM_TXISOL_READ_COMMITTED | Read Committed |
| 3 | SESAM_TXISOL_REPEATABLE_READ | Repeatable Read |
| 4 | SESAM_TXISOL_SERIALIZABLE | Serializable |
Table 2. Valid values for "Read_Only" parameter
| Value | Constant | Meaning |
|---|---|---|
| 0 | SESAM_TXREAD_READWRITE | Read/Write |
| 1 | SESAM_TXREAD_READONLY | Read-Only |
The values set by sesam_settransaction() will override the default setting specified in the SESAM configuration file.