Database Query Logging (DBQL) tables track query behavior. Each row in QryLogV contains default DBQL information for a query.
Default Row
The fields of the default row provide general query information that is typically adequate for investigating a query that is interfering with performance. When no options are specified, a default row includes:- User ID and user name under which the session being logged was initiated
- Unique ID for the process, session, and host (client) connection
- Account string, expanded as appropriate, that was current when the query completed
- First 200 characters of the query SQL statement
- CPU and I/O statistics
- Default database name that was current when the query completed
FlexThrottle
Flex Throttles automatically release a throttle to allow full usage of the system and release work from the TDWM delay queue to use these resources. This column is set to 'T' if the request was released due to the Flex Throttle feature. Otherwise, the column is NULL.
InternalRequestNum
The internal request number.
For commands other than those within a stored procedure the internal request number and the number in the RequestNum field is the same. For stored procedures invoked within a session, the internal request number increments by 1 for every request made by the stored procedure. Therefore, RequestNum is the request number of the CALL and the value in InternalRequestNum continues to increment for all other queries issued by the session.
LogonSource
Teradata recommends using alternative columns instead of the LogonSource column, if available. For information about the recommended columns for LogonSource, see "LogonSource Column Fields and Examples."
MaxAMPSpool
If you are using DBQL CPU/IO Collection algorithm 3, MaxAMPSpool is the largest peak spool usage of any AMP for this step. For other algorithms, MaxAMPSpool is the highest spool usage on any AMP at the end of the step.
MinAMPSpool
If you are using DBQL CPU/IO Collection algorithm 3, MinAMPSpool is the smallest peak spool usage of any AMP for this step. For other algorithms, MinAMPSpool is the lowest spool usage of any AMP at the end of the step.
SessionTemporalQualifier
When a DML or SELECT request refers to a temporal table but omits a temporal qualifier, the system uses the value of the session temporal qualifier. This is the session temporal qualifier in effect when the query is logged.
For example, this column uses the ANSIQUALIFIER value if the session temporal qualifier is set to ANSIQUALIFIER for ANSI temporal tables.
TacticalRequest
This column in DBC.DBQLogTbl table identifies the tactical SQL requests.
Possible Values for CacheFlag
This column is blank if the query is not found in the request cache. Possible values include:
| Value | Description |
|---|---|
| T | Query execution plan is generic and found in the request cache. |
| S | Query plan is specific (either a static or dynamic plan). |
| G | Query plan is generic and not in the request cache but is a candidate for caching in subsequent runs of the same query. |
| A |
If a Specific Always decision is taken. That is, for each query USING values are peeked during request parsing. The optimizer may choose a dynamic plan with results feedback. |
| D | Generic plan from the request cache is used for the request execution. |
| P | Request is parsed to generate the plan by peeking the literal values. |
| N | Request is parsed to generate the plan without peeking the literal values (generic plan). |
| I | PRCE infrastructure has decided specific plan is always better and this request is ineligible for Dynamic Parametrization of Literals feature. |
| R | Query plan is dynamic plan eligible for caching and not in request cache. Cached as part of this run. |
For more information on specific plans and generic plans, see Parameterized Requests.
Possible Values for CPUDecayLevel
| Value | Description |
|---|---|
| 0 | Request is running at default priority. |
| 1 | Priority level is reduced and resource allotment is halved. |
| 2 | Priority level is reduced again, resource allotment is halved again. No future reductions. |
Possible Values for DataCollectAlg
| Value | Description |
|---|---|
| 1 | Use the classic algorithm with step adjustments. |
| 2 | Use AMP algorithm 2 (diagnostic only). |
| 3 | Use AMP algorithm 3 (includes information on aborted and parallel steps). |
Possible Values for IODecayLevel
| Value | Description |
|---|---|
| 0 | Request is running at default priority. |
| 1 | Priority level is reduced and resource allotment is halved. |
| 2 | Priority level is reduced again, resource allotment is halved again. No future reductions. |
Possible Values for LockLevel
- NOLOCK
- ACCESS
- READ
- WRITE
- EXCLUSIVE
- UNKNOWN
Possible Values for QueryBand
| Value | Description |
|---|---|
| T | Transaction query band pairs. |
| S | Session query band pairs. |
| P | Profile query band pairs. |
Possible Values for QueryRedriven
| Value | Description |
|---|---|
| E | The request was reparsed due to an internal Parser error. |
| M | The request was reparsed due to an internal Parser memory limit. |
| R | The request was redriven due to a database restart. |
| N | The request was not redriven or reparsed. |
Possible Values for RedriveKind
| Value | Description |
|---|---|
| ' ' | Not participating in redrive. |
| MN | Memory-based protection, no fallback spool. |
| MF | Memory-based protection, with fallback spool. |
| DN | Dictionary-based protection, no fallback spool. |
| DF | Dictionary-based protection, with fallback spool. |
Possible Values for RequestMode
| Value | Description |
|---|---|
| P | Prep: Prepare mode (P). |
| E | Exec: Run mode (E). |
| B | Both: Prepare and run mode (B). |
| S | PrepS: Prepare, supporting parameterized SQL (S). |
Possible Values for StatementGroup
- DDL ALTER
- DDL CREATE
- DDL GRANT
If the statement has only one DML statement or multiple DML statements that are all of the same type, StatementGroup indicates the type. For example if there are three DELETE statements in a request, StatementGroup reports:
DML DELETE
- DML INSERT
- DML INSERT/SELECT
- DML UPDATE
- DML MERGE INTO
- SELECT
In a multiple-statement request with different types of DML statements, you see a list showing the number of statements of each type in the request. For example, a request with one insert and two update statements appear as:
DML Del=0 Ins=1 InsSel=0 Upd=2 Sel=0 MergeInto=0Possible Values for ThrottleBypassed
ThrottleBypassed indicates whether an active request is active solely due to the ThrottleBypass ruleset attribute. This attribute overrides the throttle limits if the session owning the request has an object lock higher than the Access level. Possible values include:
| Value | Description |
|---|---|
| 0 | ThrottleBypass ruleset attribute is not set. |
| 1 | ThrottleBypass ruleset attribute is set. |
Possible Values for TTGranularity
| Value | Description |
|---|---|
| LOGICALROW | Row is timestamped with the time the row is processed by the AMP. |
| REQUEST | Row is timestamped with the time the request is submitted. |
| TRANSACTION | Row is timestamped with the time when the first non-locking reference is made to a temporal table, or when the built-in function TEMPORAL_TIMESTAMP is first accessed during the transaction. |
Possible Values for UtilityInfoAvailable
UtilityInfoAvailable indicates whether an SQL request has utility information available in DBQLUtilityTbl. Possible values include:
| Value | Description |
|---|---|
| Y | SQL request has utility information (for example, from DSA or the control SQL session of a load or export utility) logged in the DBQLUtilityTbl table. |
| N | SQL request does not have utility information logged in the DBQLUtilityTbl table. |