Sources oF FUNCTION, PROCEDURE

SELECT  T.*
FROM    (SELECT N.NSPNAME                   AS SCHEMA_NAME
        ,       P.PRONAME                   AS OBJECT_NAME
        ,       PG_GET_FUNCTIONDEF(P.OID)   AS SOURCE

        FROM PG_CATALOG.PG_PROC P
        JOIN PG_CATALOG.PG_NAMESPACE N  ON  N.OID = P.PRONAMESPACE
        WHERE N.NSPNAME NOT IN ('information_schema', 'pg_catalog')
        ) T
WHERE T.SCHEMA_NAME IN('blog')
-- AND UPPER(T.OBJECT_NAME) LIKE '%' || UPPER('keyword') || '%'
AND UPPER(T.SOURCE) LIKE '%' || UPPER('keyword') || '%'
;

Sources of VIEW

SELECT  T.*
FROM   (SELECT  V.SCHEMANAME                AS SCHEMA_NAME
        ,       V.VIEWNAME                  AS VIEW_NAME
        ,       V.DEFINITION                AS SOURCE
        FROM PG_CATALOG.PG_VIEWS V
        WHERE V.SCHEMANAME NOT IN ('information_schema', 'pg_catalog')
        ) T
WHERE T.SCHEMA_NAME IN('blog')
-- AND UPPER(T.VIEW_NAME) LIKE '%' || UPPER('keyword') || '%'
AND UPPER(T.SOURCE) LIKE '%' || UPPER('keyword') || '%'
;

Table's Column list

SELECT  T.*
FROM   (SELECT  NSP.NSPNAME                                                                 AS SCHEMA_NAME
      --,       TBL.OID
        ,       TBL.RELNAME                                                                 AS TABLE_NAME
      --,       OBJ_DESCRIPTION((NSP.NSPNAME || '.' || TBL.RELNAME)::REGCLASS, 'pg_class')  AS TABLE_DESC
        
        ,       COL.ATTNUM                                                                  AS COLUMN_ID
      --,       COL.ATTRELID
        ,       COL.ATTNAME                                                                 AS COLUMN_NAME
        ,       CMT.DESCRIPTION                                                             AS COLUMN_DESC
      --,       COL.ATTTYPID
        ,       COL.ATTNOTNULL                                                              AS NOT_NULL
        ,       FORMAT_TYPE(COL.ATTTYPID, COL.ATTTYPMOD)                                    AS DATA_TYPE
        ,       PG_GET_EXPR(DEF.ADBIN, DEF.ADRELID)                                         AS DEFAULT_VALUE
        
        FROM PG_CATALOG.PG_NAMESPACE NSP
        JOIN PG_CATALOG.PG_CLASS TBL                    ON  TBL.RELNAMESPACE    = NSP.OID
        JOIN PG_CATALOG.PG_ATTRIBUTE COL                ON  COL.ATTRELID        = TBL.OID
                                                        AND COL.ATTNUM          > 0
                                                        
        LEFT OUTER JOIN PG_CATALOG.PG_ATTRDEF DEF       ON  DEF.ADRELID         = COL.ATTRELID
                                                        AND DEF.ADNUM           = COL.ATTNUM
        
        LEFT OUTER JOIN PG_CATALOG.PG_DESCRIPTION CMT   ON  CMT.OBJOID          = COL.ATTRELID
                                                        AND CMT.OBJSUBID        = COL.ATTNUM

        ) T

WHERE T.SCHEMA_NAME = 'public' 
--AND T.TABLE_NAME LIKE 'blog%'

ORDER BY T.TABLE_NAME, T.COLUMN_ID
;

Constraints of Tables

SELECT  T.TABLE_NAME
,       T.CONSTRAINT_NANE
,       CASE T.CONTYPE
            WHEN 'p' THEN 'PRIMARY KEY'
            WHEN 'u' THEN 'UNIQUE'
            WHEN 'f' THEN 'FOREIGN KEY'
        END                                     AS CONSTRAINT_TYPE
,       'ALTER TABLE'
||      ' '
||      T.SCHEMA_NAME
||      '.'
||      T.TABLE_NAME
||      ' '
||      'ADD CONSTRAINT'
||      ' '
||      T.CONSTRAINT_NANE
||      ' '
||      CASE T.CONTYPE
            WHEN 'p' THEN 'PRIMARY KEY'
            WHEN 'u' THEN 'UNIQUE'
            WHEN 'f' THEN 'FOREIGN KEY'
        END
||      ' ('
||      T.COLUMN_NAMES
||      ') '
||      CASE T.CONTYPE
            WHEN 'p' THEN 'USING INDEX TABLESPACE tbs01;'
            WHEN 'u' THEN 'USING INDEX TABLESPACE tbs01;'
            WHEN 'f' THEN 'REFERENCES ' || T.SCHEMA_NAME || '.' || T.REF_TABLE_NAME || ' (' || T.REF_COLUMN_NAMES || ');'
        END                                     AS CREATE_SCRIPT

,       'ALTER TABLE'
||      ' '
||      T.SCHEMA_NAME
||      '.'
||      T.TABLE_NAME
||      ' '
||      'DROP CONSTRAINT IF EXISTS'
||      ' '
||      T.CONSTRAINT_NANE
||      ';'                                     AS DROP_SCRIPT

FROM   (SELECT  CST.CONNAMESPACE::REGNAMESPACE::TEXT    AS SCHEMA_NAME
        ,       CST.CONRELID::REGCLASS::TEXT            AS TABLE_NAME
        ,       CST.CONNAME                             AS CONSTRAINT_NANE
        ,       CST.CONTYPE
      --,       CST.OID                                 AS CON_OID
      --,       CST.CONRELID                            AS TABLE_OID
      --,       CST.CONINDID                            AS INDEX_OID
      --,       CST.CONKEY 
      --,       CST.CONFKEY 
        ,      (SELECT ARRAY_TO_STRING(ARRAY_AGG(COL.ATTNAME), ', ')
                FROM UNNEST(CST.CONKEY) AS CAC(ATT_OID)
                JOIN PG_CATALOG.PG_ATTRIBUTE COL    ON  COL.ATTRELID    = CST.CONRELID
                                                    AND COL.ATTNUM      = CAC.ATT_OID)
                                                        AS COLUMN_NAMES
                                                        
        ,       CST.CONFRELID::REGCLASS::TEXT           AS REF_TABLE_NAME
        ,      (SELECT ARRAY_TO_STRING(ARRAY_AGG(COL.ATTNAME), ', ')
                FROM UNNEST(CST.CONFKEY) AS CAC(ATT_OID)
                JOIN PG_CATALOG.PG_ATTRIBUTE COL    ON  COL.ATTRELID    = CST.CONFRELID
                                                    AND COL.ATTNUM      = CAC.ATT_OID)
                                                        AS REF_COLUMN_NAMES
        FROM PG_CATALOG.PG_CONSTRAINT CST
        ) T
WHERE T.SCHEMA_NAME = 'public'
AND T.CONTYPE IN ('p', 'u', 'f')
AND T.TABLE_NAME = 'blog_post'
;