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26.12.10 Performance Schema User-Defined Variable Tables
The Performance Schema provides a
user_variables_by_thread
table that
exposes user-defined variables. These are variables defined
within a specific session and include a @
character preceding the name; see
Section 9.4, “User-Defined Variables”.
The user_variables_by_thread
table
contains these columns:
THREAD_ID
The thread identifier of the session in which the variable is defined.
VARIABLE_NAME
The variable name, without the leading
@
character.VARIABLE_VALUE
The variable value.
The user_variables_by_thread
table
has these indexes:
Primary key on (
THREAD_ID
,VARIABLE_NAME
)
TRUNCATE TABLE
is not permitted
for the user_variables_by_thread
table.
Document created the 26/06/2006, last modified the 26/10/2018
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