Build WHERE predicates that select intended rows, handle comparison boundaries, and verify the result against included and excluded cases.

What you will be able to do

Distinguish candidate rows from filter predicate in a realistic filter rows with where case.
Interpret the database evidence and boundary associated with input value.
Choose an appropriate action involving filtered result without exceeding the named data scope.
Verify predicate inspection through an observable database result and reproducible handoff.

Frame Filter Rows with WHERE

Build WHERE predicates that select intended rows, handle comparison boundaries, and verify the result against included and excluded cases.

A queue report should show open tickets with priority high or critical. Closed tickets and lower priorities must remain outside the result even when their titles look urgent.

Keep the database target, stored state, input values, expected result, and allowed change scope separate. Begin in an isolated practice database, inspect before modifying, and preserve enough evidence to repeat the decision.

Candidate rows

The FROM result provides candidate rows before WHERE removes nonmatches. Within filter rows with where, this concept answers a separate data question and retains its own observable evidence.

Identify the table and row population before writing the filter. Apply that action to the named database case before broadening the query or changing more stored state.

Respect this boundary: do not assume a filter repairs incorrect stored data. The required result is specific: the candidate set comes from the intended ticket table.

Filter predicate

A WHERE predicate evaluates a condition for each candidate row. Within filter rows with where, this concept answers a separate data question and retains its own observable evidence.

Express the approved status and priority conditions with explicit operators. Apply that action to the named database case before broadening the query or changing more stored state.

Respect this boundary: do not rely on title wording as a priority rule. The required result is specific: only rows satisfying the complete predicate remain.

Input value

Comparison values must be compatible with the column meaning and type. Within filter rows with where, this concept answers a separate data question and retains its own observable evidence.

Use status and priority values exactly as the schema stores them. Apply that action to the named database case before broadening the query or changing more stored state.

Respect this boundary: do not compare a date or number through an accidental text format. The required result is specific: the predicate evaluates comparable values without unintended conversion.

Filtered result

The filtered result contains rows where the WHERE condition is true. Within filter rows with where, this concept answers a separate data question and retains its own observable evidence.

Check known included and excluded tickets against the returned set. Apply that action to the named database case before broadening the query or changing more stored state.

Respect this boundary: do not validate a filter with one matching example only. The required result is specific: high-priority open tickets appear while nonmatches stay absent.

Predicate inspection

Predicate inspection tests each logical branch and important boundary value. Within filter rows with where, this concept answers a separate data question and retains its own observable evidence.

Create a small expectation table before comparing the query output. Apply that action to the named database case before broadening the query or changing more stored state.

Respect this boundary: do not widen the condition merely to increase row count. The required result is specific: observed inclusion and exclusion match the stated queue rule.

Apply Filter Rows with WHERE to One Case

Use the case as a bounded database task: A queue report should show open tickets with priority high or critical. Closed tickets and lower priorities must remain outside the result even when their titles look urgent.

First, identify the table and row population before writing the filter. Then, express the approved status and priority conditions with explicit operators. Keep both observations with the target database and expected result before choosing the next statement.

Next, use status and priority values exactly as the schema stores them. After that, check known included and excluded tickets against the returned set. Finish only after you create a small expectation table before comparing the query output.

Recap Before Practice and Prove

Candidate rows: The FROM result provides candidate rows before WHERE removes nonmatches. In the database case, identify the table and row population before writing the filter. Preserve the boundary: do not assume a filter repairs incorrect stored data.

Filter predicate: A WHERE predicate evaluates a condition for each candidate row. In the database case, express the approved status and priority conditions with explicit operators. Preserve the boundary: do not rely on title wording as a priority rule.

Input value: Comparison values must be compatible with the column meaning and type. In the database case, use status and priority values exactly as the schema stores them. Preserve the boundary: do not compare a date or number through an accidental text format.

Filtered result: The filtered result contains rows where the WHERE condition is true. In the database case, check known included and excluded tickets against the returned set. Preserve the boundary: do not validate a filter with one matching example only.

Predicate inspection: Predicate inspection tests each logical branch and important boundary value. In the database case, create a small expectation table before comparing the query output. Preserve the boundary: do not widen the condition merely to increase row count.