caseWhen | TanStack DB Español

Call Signature

function caseWhen<C1, V1>(condition1, value1): CaseWhenResult<[V1], false>;

Defined in: packages/db/src/query/builder/functions.ts:408

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Arguments are evaluated as condition/value pairs followed by an optional default value. Scalar branch values return a query expression and can be used in expression contexts like select, where, orderBy, groupBy, having, and equality join operands. If no scalar branch matches and no default is provided, the result is null.

When a branch value is a projection object, caseWhen becomes a select-only projection value. Projection branches can include nested fields, ref spreads, and includes. If no projection branch matches and no default is provided, the result is undefined.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

Parameters

condition1

C1

value1

V1

Returns

CaseWhenResult<[V1], false>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, D>(
   condition1, 
   value1, 
defaultValue): CaseWhenResult<[V1, D], true>;

Defined in: packages/db/src/query/builder/functions.ts:412

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

D

D extends CaseWhenValue

Parameters

condition1

C1

value1

V1

defaultValue

D

Returns

CaseWhenResult<[V1, D], true>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2>(
   condition1, 
   value1, 
   condition2, 
value2): CaseWhenResult<[V1, V2], false>;

Defined in: packages/db/src/query/builder/functions.ts:417

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

Returns

CaseWhenResult<[V1, V2], false>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, D>(
   condition1, 
   value1, 
   condition2, 
   value2, 
defaultValue): CaseWhenResult<[V1, V2, D], true>;

Defined in: packages/db/src/query/builder/functions.ts:428

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

D

D extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

defaultValue

D

Returns

CaseWhenResult<[V1, V2, D], true>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
value3): CaseWhenResult<[V1, V2, V3], false>;

Defined in: packages/db/src/query/builder/functions.ts:441

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

Returns

CaseWhenResult<[V1, V2, V3], false>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3, D>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
   value3, 
defaultValue): CaseWhenResult<[V1, V2, V3, D], true>;

Defined in: packages/db/src/query/builder/functions.ts:456

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

D

D extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

defaultValue

D

Returns

CaseWhenResult<[V1, V2, V3, D], true>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3, C4, V4>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
   value3, 
   condition4, 
value4): CaseWhenResult<[V1, V2, V3, V4], false>;

Defined in: packages/db/src/query/builder/functions.ts:473

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

C4

C4 extends ExpressionLike

V4

V4 extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

condition4

C4

value4

V4

Returns

CaseWhenResult<[V1, V2, V3, V4], false>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3, C4, V4, D>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
   value3, 
   condition4, 
   value4, 
defaultValue): CaseWhenResult<[V1, V2, V3, V4, D], true>;

Defined in: packages/db/src/query/builder/functions.ts:492

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

C4

C4 extends ExpressionLike

V4

V4 extends CaseWhenValue

D

D extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

condition4

C4

value4

V4

defaultValue

D

Returns

CaseWhenResult<[V1, V2, V3, V4, D], true>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3, C4, V4, C5, V5>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
   value3, 
   condition4, 
   value4, 
   condition5, 
value5): CaseWhenResult<[V1, V2, V3, V4, V5], false>;

Defined in: packages/db/src/query/builder/functions.ts:513

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

C4

C4 extends ExpressionLike

V4

V4 extends CaseWhenValue

C5

C5 extends ExpressionLike

V5

V5 extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

condition4

C4

value4

V4

condition5

C5

value5

V5

Returns

CaseWhenResult<[V1, V2, V3, V4, V5], false>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3, C4, V4, C5, V5, D>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
   value3, 
   condition4, 
   value4, 
   condition5, 
   value5, 
defaultValue): CaseWhenResult<[V1, V2, V3, V4, V5, D], true>;

Defined in: packages/db/src/query/builder/functions.ts:536

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

C4

C4 extends ExpressionLike

V4

V4 extends CaseWhenValue

C5

C5 extends ExpressionLike

V5

V5 extends CaseWhenValue

D

D extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

condition4

C4

value4

V4

condition5

C5

value5

V5

defaultValue

D

Returns

CaseWhenResult<[V1, V2, V3, V4, V5, D], true>

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})

Call Signature

function caseWhen<C1, V1, C2, V2, C3, V3, C4, V4, C5, V5>(
   condition1, 
   value1, 
   condition2, 
   value2, 
   condition3, 
   value3, 
   condition4, 
   value4, 
   condition5, 
   value5, 
   condition6, 
   value6, ...
   rest): any;

Defined in: packages/db/src/query/builder/functions.ts:561

Returns the value for the first matching condition, similar to SQL CASE WHEN.

Type Parameters

C1

C1 extends ExpressionLike

V1

V1 extends CaseWhenValue

C2

C2 extends ExpressionLike

V2

V2 extends CaseWhenValue

C3

C3 extends ExpressionLike

V3

V3 extends CaseWhenValue

C4

C4 extends ExpressionLike

V4

V4 extends CaseWhenValue

C5

C5 extends ExpressionLike

V5

V5 extends CaseWhenValue

Parameters

condition1

C1

value1

V1

condition2

C2

value2

V2

condition3

C3

value3

V3

condition4

C4

value4

V4

condition5

C5

value5

V5

condition6

ExpressionLike

value6

CaseWhenValue

rest

...CaseWhenValue[]

Returns

any

Examples

caseWhen(gt(user.age, 18), `adult`, `minor`)

caseWhen(
  gt(user.age, 65),
  `senior`,
  gt(user.age, 18),
  `adult`,
  `minor`,
)

caseWhen(gt(user.age, 18), {
  ...user,
  posts: q
    .from({ post: postsCollection })
    .where(({ post }) => eq(post.userId, user.id)),
})