The following sections provide an introduction to the data manipulation language (DML) used by the database system.
Every SQL statement that manipulates data implicitly sets an EXCLUSIVE lock (see
transactions) for each inserted, updated, or deleted row.Whenever a user's transaction holds too many row locks on a table, the database system attempts to convert these row locks into a table lock. If this causes collisions with other locks, further row locks are requested. This means that table locks are obtained without waiting periods. The limit beyond which the database system attempts to transform row locks into table locks depends on the installation parameter MAXLOCKS, which indicates the maximum number of possible lock entries allowed for a transaction.
SQL statements for data manipulation
INSERT statement | UPDATE statement | DELETE statement |
NEXT STAMP statement | CALL statement |