Documentation
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Overview ¶
Package types holds the custom column types Momo understands: each is a Codec, so database/sql can scan it, drivers can bind it and the schema layer can name its SQL type per dialect.
Index ¶
Constants ¶
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Variables ¶
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Functions ¶
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Types ¶
type Codec ¶
Codec is the custom-type contract: database/sql scanning, driver value encoding and the SQL type per dialect.
type Date ¶
Date is a calendar date (no time zone): date on PostgreSQL, TEXT 'YYYY-MM-DD' on SQLite and MySQL.
PostgreSQL also has the special dates 'infinity' and '-infinity'. Set Infinity or NegInfinity to write one; Scan sets the flag and leaves Time zero when it reads one. Time is ignored while a flag is set. SQLite and MySQL have no special dates: Momo rejects a Date with a flag set there with ErrValidation. IsFinite reports whether the value is an ordinary date.
func (Date) IsFinite ¶ added in v0.8.0
IsFinite reports whether d is an ordinary calendar date, not infinity or -infinity.
type Hstore ¶
Hstore is map[string]*string: hstore on PostgreSQL, TEXT JSON on SQLite. A nil value pointer is an hstore NULL.
func (*Hstore) Scan ¶
Scan accepts the PostgreSQL hstore text form or a JSON object (string or []byte). Duplicate keys in hstore text resolve first-wins, as PostgreSQL does. Scan(nil) returns an error: Hstore models a NOT NULL column, so use a *Hstore or a Null wrapper for nullable columns.
type JSON ¶
type JSON[T any] struct{ V T }
JSON[T] stores any JSON-encodable T: jsonb on PostgreSQL, TEXT on SQLite. A nil map, slice or pointer encodes as the JSON literal null, an empty one as {} or []; Scan restores the same distinction.
type Numeric ¶ added in v0.8.0
Numeric is an exact decimal number: numeric on PostgreSQL, TEXT on SQLite and MySQL. The digits live in a string, so no precision is lost to binary floating point and Momo needs no decimal library.
Decimal holds a finite value such as "-12.50" or "0.000000001"; empty means 0. PostgreSQL numeric also holds NaN and the infinities: set NaN, Infinity or NegInfinity (at most one, with Decimal empty) to write one, and Scan sets the flag when it reads one. SQLite and MySQL have no such values: Momo rejects a Numeric with a flag set there with ErrValidation. IsFinite reports whether the value is an ordinary number.
NaN has been a numeric value for a long time, but Infinity and -Infinity need PostgreSQL 14 or later; Momo's CI covers PostgreSQL 16 and 17. An older server rejects them with a database error.
Numeric does no arithmetic. Use a decimal library for that, or let the database do it. Scan does not accept a pgtype.Numeric; read the column as Numeric, or convert with its String form.
func NumericFromFloat64 ¶ added in v0.9.0
NumericFromFloat64 returns the Numeric holding f written as the shortest decimal that reads back as the same float64 (strconv.FormatFloat with 'f' and precision -1), without an exponent. A float64 is already binary, so this is the float's shortest representation, not an exact conversion of its bits: 0.1 gives "0.1", not the long expansion of the nearest binary fraction. Use it to bring a float you already have into a numeric column; it cannot repair precision a float already lost. NaN and the infinities return an error; set the NaN, Infinity or NegInfinity flag by hand to store one.
func NumericFromInt64 ¶ added in v0.9.0
NumericFromInt64 returns the Numeric holding n exactly.
func ParseNumeric ¶ added in v0.8.0
ParseNumeric parses PostgreSQL numeric text: an optionally signed decimal ("12", "-1.5", ".5", "7."), or NaN, Infinity or -Infinity (also written inf, any case). Surrounding spaces are ignored; an exponent is not accepted.
func (Numeric) IsFinite ¶ added in v0.8.0
IsFinite reports whether n is an ordinary number: not NaN and not infinite.
func (Numeric) IsInfinite ¶ added in v0.8.0
IsInfinite reports whether n is Infinity or -Infinity.
func (*Numeric) Scan ¶ added in v0.8.0
Scan accepts the text form as string or []byte, an int64, or a float64 (what SQLite returns for an aggregate or an expression). A float64 is written in plain decimal form without exponent, with the shortest digits that read back the same; NaN and the infinities set their flags. Scan(nil) returns an error: use a *Numeric for a nullable column.
func (Numeric) Sign ¶ added in v0.8.0
Sign returns -1, 0 or +1 for a negative, zero or positive n. Infinity is +1, -Infinity is -1 and NaN is 0.
type TSQuery ¶ added in v0.4.0
type TSQuery string
TSQuery is a PostgreSQL full-text query: tsquery on PostgreSQL, TEXT on SQLite. It is mostly the result type of the query builders (fts.ToQuery, fts.WebsearchToQuery, ...), but a column can hold one too (stored searches).
type TSVector ¶ added in v0.4.0
type TSVector string
TSVector is a PostgreSQL full-text document: tsvector on PostgreSQL, TEXT on SQLite (which has no full-text search through Momo). Its value is the text form PostgreSQL prints, for example 'cat':3 'fat':2, with the lexemes sorted and normalized by the server.
A column of this type is usually maintained by a trigger declared through MomoConfig and is read-only for the application; the full-text expression builders (fts.Match, fts.ToVector, fts.RankCD, ...) take it as an operand.
type TimeOfDay ¶
type TimeOfDay struct{ Nanos int64 }
TimeOfDay is a time of day: time on PostgreSQL, TEXT 'HH:MM:SS.uuuuuu' on SQLite.
func (*TimeOfDay) Scan ¶
Scan accepts 'HH:MM:SS' with an optional fraction of 1 to 9 digits (string or []byte). PostgreSQL's 24:00:00 is read as the last nanosecond of the day. Scan(nil) returns an error: use a pointer or a Null wrapper for nullable columns. Integer sources are rejected because drivers disagree on their unit.
type UUID ¶
type UUID [16]byte
UUID is a 16-byte identifier: uuid on PostgreSQL, TEXT canonical form on SQLite.
func ParseUUID ¶
ParseUUID parses the canonical 36-character form (dashes at 8, 13, 18, 23) or 32 bare hex digits.
func (*UUID) Scan ¶
Scan accepts the canonical 36-character form or 32 bare hex digits (string or []byte), or exactly 16 raw bytes. Any other length or character is an error.
Source Files